COORDINATION CHEMISTRY OF ORGANOTIN (IV) COMPLEXES WITH NN DONOR LIGANDS
Cynthia Anak Paul Sebli
Bachelor of Science with Honours (Resource Chemistry)
2006
COORDINATION CHEMISTRY OF ORGANOTIN(IV) COMPLEXES WITH NN DONOR LIGANDS
CYNTHIA ANAK PAUL SEBLI
This project is submilted in part ia l fulfillment of the requirements for the degree of Bachelor of Science with Honows (Resource Chemistry)
Facult y of Resource Science and Technology UN IVERSITI MALAYSIA SARAWAK
2006
DECLARAnON
No portion o f the wo rk referred to this dissert at ion has been submitted in support o f an
application for another degree o f quali fication of this or any o thtr university of institu tion of
higher learning
Cynthia anak Paul Sebl i
Program of Reso urce Chemistry
Faculty of Resource Science and Techno logy
Uni versiti Malays ia Sarawak
ACKNOWLEDGEMENTS
I wo uld like to thank my supervisor Dr Md Abu Affan Resource Chemistry Program
UN IMAS for hi s constant guidance and continuous encouragement without which this work
would no t have been possible I also would like to express my appreciation to Mr Liew Yew
Zion MSc student of Resource Chemistry Program UN IMAS for his occasional help to
complete this report I would like to express my sincere thanks to all staffs of this chemistry
program for their inspiration and valuable ad vice Thank you very much to the Department of
Chemisrty Rajs hahi University Bangladesh for CHN analys is finally I would li ke to express
my grat it ude to my parents brother and sisters who were the constant so urce of inspiration
during the course of this project research work T hanks a lot to all my friends for encouraging
me co nstantly Last but no t least to those who involved d irectly or indirectly in giving hand to
me in completing this project and writing this report though you are unknown by name thank
you very much
Only GOD knows how to reward all of yo u Thank you
II
tgtasal Khldmlll Maklumat AkamIk ~tSrn 11 LHS SAIt~WAJ(
TABLE OF CONTENT Pages
LIST OF TABLES IV
LIST OF FIGURES V
ABSTRACT VI
10 Introduction 11 Coordination compounds of o rganolin(JV) ions 1 2 Objectives
20 Literature Review 2 21 Characterist ic ofN - do no r ligands 2 22 Bidentale nitrogen (NN-) donor ligands 3
23 Trid entate nitrogen (NNN -) donor ligands 5
24 Tetradentate nit rogen (NNNN-) donor ligands 5 25 Chelate Effect 6 26 Organot in(l V) complexes with NN donor ligands 7
30 Materials and Methods 13 3 I General Methods 13 32 Measurement 13 33 Synthes is ofligand (1) and it s orgallotin(JV) complexes (3-7) 14
33 1 Preparatio n of 2-acetylpyridillebenzo phenoneazine [C20 HI )N3] co ntaining NN-donor atoms (1 )
332 Synthesis of [Me2SnCh(C2o H I7NJ)] (3) 333 Synthesis of [Bu2S nClJ(C2HHI)N3)] (4) 33 4 Synthesis of (PhSnC I3(C2oHI )N3) ] (5) 335 Synthesis of(BuSnCI3(C1oH )N3)] (6) 336 Synthesis of[Bu3SnC I(C2oHI7NJ)] (7)
34 Synthes is o f ligand (2) and it s dio rganotin( lV) complexes (8-10) 341 Preparation of 2 -acetylpyridinep henylh yd razo ne [CI1 HI3
dono r atoms (2) 342 Synthesis of(Me2SnCI1(CuHuN3)] (8) 34 3 Synthes is of(Bu2SnCh(CIlHuN3)] (9) 344 Synthesis of [Ph2SnCh(C13 HIJN3)] (10)
40 Results and Discussion 4 1 Phys ical and ana lytica l data
14 15 15 15 15 16 17
3] containing 17 18 18 18
19 2 1
42 Spectroscopic studies of ligands (1-2) and their organotin(lV) corl1p lexes (3-10) 23 42 1 UV-Vis resu lts of ligand (1) and its organot in(lV) complexes (3-7) 23 42 2 IR spectral of liga nd ( 1) and its organotin(IV) complexes (3-7) 26 423 IR spectral 0 f ligand (2) and its organot in(fV) complexes (8-10) 3 I
50 Conclusion 38
60 Suggestion for Future Research 38
70 References 39
11
Pages LIST OF TABLES
Table I Elemental analys is fo r the ligands (1-2) and their organotin(l V) complexes (3-10) 21 Table 2 Mo lar conductance va lues fo r organotin(I V) complexes (3-10) 22 Table 3 The Am (nm) peaks of ligand (I ) and it s organotin(IV) complexes (3-7) 23 Table 4 Main IR data of the liga nd (1) and its o rgano tin(IV) complexes (3-7) (em) 28 Table 5 Ma in IR data of the liga nd (2) and it s dio rgano tin(lV) complexes (8-10) (em) 33
IV
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
COORDINATION CHEMISTRY OF ORGANOTIN(IV) COMPLEXES WITH NN DONOR LIGANDS
CYNTHIA ANAK PAUL SEBLI
This project is submilted in part ia l fulfillment of the requirements for the degree of Bachelor of Science with Honows (Resource Chemistry)
Facult y of Resource Science and Technology UN IVERSITI MALAYSIA SARAWAK
2006
DECLARAnON
No portion o f the wo rk referred to this dissert at ion has been submitted in support o f an
application for another degree o f quali fication of this or any o thtr university of institu tion of
higher learning
Cynthia anak Paul Sebl i
Program of Reso urce Chemistry
Faculty of Resource Science and Techno logy
Uni versiti Malays ia Sarawak
ACKNOWLEDGEMENTS
I wo uld like to thank my supervisor Dr Md Abu Affan Resource Chemistry Program
UN IMAS for hi s constant guidance and continuous encouragement without which this work
would no t have been possible I also would like to express my appreciation to Mr Liew Yew
Zion MSc student of Resource Chemistry Program UN IMAS for his occasional help to
complete this report I would like to express my sincere thanks to all staffs of this chemistry
program for their inspiration and valuable ad vice Thank you very much to the Department of
Chemisrty Rajs hahi University Bangladesh for CHN analys is finally I would li ke to express
my grat it ude to my parents brother and sisters who were the constant so urce of inspiration
during the course of this project research work T hanks a lot to all my friends for encouraging
me co nstantly Last but no t least to those who involved d irectly or indirectly in giving hand to
me in completing this project and writing this report though you are unknown by name thank
you very much
Only GOD knows how to reward all of yo u Thank you
II
tgtasal Khldmlll Maklumat AkamIk ~tSrn 11 LHS SAIt~WAJ(
TABLE OF CONTENT Pages
LIST OF TABLES IV
LIST OF FIGURES V
ABSTRACT VI
10 Introduction 11 Coordination compounds of o rganolin(JV) ions 1 2 Objectives
20 Literature Review 2 21 Characterist ic ofN - do no r ligands 2 22 Bidentale nitrogen (NN-) donor ligands 3
23 Trid entate nitrogen (NNN -) donor ligands 5
24 Tetradentate nit rogen (NNNN-) donor ligands 5 25 Chelate Effect 6 26 Organot in(l V) complexes with NN donor ligands 7
30 Materials and Methods 13 3 I General Methods 13 32 Measurement 13 33 Synthes is ofligand (1) and it s orgallotin(JV) complexes (3-7) 14
33 1 Preparatio n of 2-acetylpyridillebenzo phenoneazine [C20 HI )N3] co ntaining NN-donor atoms (1 )
332 Synthesis of [Me2SnCh(C2o H I7NJ)] (3) 333 Synthesis of [Bu2S nClJ(C2HHI)N3)] (4) 33 4 Synthesis of (PhSnC I3(C2oHI )N3) ] (5) 335 Synthesis of(BuSnCI3(C1oH )N3)] (6) 336 Synthesis of[Bu3SnC I(C2oHI7NJ)] (7)
34 Synthes is o f ligand (2) and it s dio rganotin( lV) complexes (8-10) 341 Preparation of 2 -acetylpyridinep henylh yd razo ne [CI1 HI3
dono r atoms (2) 342 Synthesis of(Me2SnCI1(CuHuN3)] (8) 34 3 Synthes is of(Bu2SnCh(CIlHuN3)] (9) 344 Synthesis of [Ph2SnCh(C13 HIJN3)] (10)
40 Results and Discussion 4 1 Phys ical and ana lytica l data
14 15 15 15 15 16 17
3] containing 17 18 18 18
19 2 1
42 Spectroscopic studies of ligands (1-2) and their organotin(lV) corl1p lexes (3-10) 23 42 1 UV-Vis resu lts of ligand (1) and its organot in(lV) complexes (3-7) 23 42 2 IR spectral of liga nd ( 1) and its organotin(IV) complexes (3-7) 26 423 IR spectral 0 f ligand (2) and its organot in(fV) complexes (8-10) 3 I
50 Conclusion 38
60 Suggestion for Future Research 38
70 References 39
11
Pages LIST OF TABLES
Table I Elemental analys is fo r the ligands (1-2) and their organotin(l V) complexes (3-10) 21 Table 2 Mo lar conductance va lues fo r organotin(I V) complexes (3-10) 22 Table 3 The Am (nm) peaks of ligand (I ) and it s organotin(IV) complexes (3-7) 23 Table 4 Main IR data of the liga nd (1) and its o rgano tin(IV) complexes (3-7) (em) 28 Table 5 Ma in IR data of the liga nd (2) and it s dio rgano tin(lV) complexes (8-10) (em) 33
IV
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
DECLARAnON
No portion o f the wo rk referred to this dissert at ion has been submitted in support o f an
application for another degree o f quali fication of this or any o thtr university of institu tion of
higher learning
Cynthia anak Paul Sebl i
Program of Reso urce Chemistry
Faculty of Resource Science and Techno logy
Uni versiti Malays ia Sarawak
ACKNOWLEDGEMENTS
I wo uld like to thank my supervisor Dr Md Abu Affan Resource Chemistry Program
UN IMAS for hi s constant guidance and continuous encouragement without which this work
would no t have been possible I also would like to express my appreciation to Mr Liew Yew
Zion MSc student of Resource Chemistry Program UN IMAS for his occasional help to
complete this report I would like to express my sincere thanks to all staffs of this chemistry
program for their inspiration and valuable ad vice Thank you very much to the Department of
Chemisrty Rajs hahi University Bangladesh for CHN analys is finally I would li ke to express
my grat it ude to my parents brother and sisters who were the constant so urce of inspiration
during the course of this project research work T hanks a lot to all my friends for encouraging
me co nstantly Last but no t least to those who involved d irectly or indirectly in giving hand to
me in completing this project and writing this report though you are unknown by name thank
you very much
Only GOD knows how to reward all of yo u Thank you
II
tgtasal Khldmlll Maklumat AkamIk ~tSrn 11 LHS SAIt~WAJ(
TABLE OF CONTENT Pages
LIST OF TABLES IV
LIST OF FIGURES V
ABSTRACT VI
10 Introduction 11 Coordination compounds of o rganolin(JV) ions 1 2 Objectives
20 Literature Review 2 21 Characterist ic ofN - do no r ligands 2 22 Bidentale nitrogen (NN-) donor ligands 3
23 Trid entate nitrogen (NNN -) donor ligands 5
24 Tetradentate nit rogen (NNNN-) donor ligands 5 25 Chelate Effect 6 26 Organot in(l V) complexes with NN donor ligands 7
30 Materials and Methods 13 3 I General Methods 13 32 Measurement 13 33 Synthes is ofligand (1) and it s orgallotin(JV) complexes (3-7) 14
33 1 Preparatio n of 2-acetylpyridillebenzo phenoneazine [C20 HI )N3] co ntaining NN-donor atoms (1 )
332 Synthesis of [Me2SnCh(C2o H I7NJ)] (3) 333 Synthesis of [Bu2S nClJ(C2HHI)N3)] (4) 33 4 Synthesis of (PhSnC I3(C2oHI )N3) ] (5) 335 Synthesis of(BuSnCI3(C1oH )N3)] (6) 336 Synthesis of[Bu3SnC I(C2oHI7NJ)] (7)
34 Synthes is o f ligand (2) and it s dio rganotin( lV) complexes (8-10) 341 Preparation of 2 -acetylpyridinep henylh yd razo ne [CI1 HI3
dono r atoms (2) 342 Synthesis of(Me2SnCI1(CuHuN3)] (8) 34 3 Synthes is of(Bu2SnCh(CIlHuN3)] (9) 344 Synthesis of [Ph2SnCh(C13 HIJN3)] (10)
40 Results and Discussion 4 1 Phys ical and ana lytica l data
14 15 15 15 15 16 17
3] containing 17 18 18 18
19 2 1
42 Spectroscopic studies of ligands (1-2) and their organotin(lV) corl1p lexes (3-10) 23 42 1 UV-Vis resu lts of ligand (1) and its organot in(lV) complexes (3-7) 23 42 2 IR spectral of liga nd ( 1) and its organotin(IV) complexes (3-7) 26 423 IR spectral 0 f ligand (2) and its organot in(fV) complexes (8-10) 3 I
50 Conclusion 38
60 Suggestion for Future Research 38
70 References 39
11
Pages LIST OF TABLES
Table I Elemental analys is fo r the ligands (1-2) and their organotin(l V) complexes (3-10) 21 Table 2 Mo lar conductance va lues fo r organotin(I V) complexes (3-10) 22 Table 3 The Am (nm) peaks of ligand (I ) and it s organotin(IV) complexes (3-7) 23 Table 4 Main IR data of the liga nd (1) and its o rgano tin(IV) complexes (3-7) (em) 28 Table 5 Ma in IR data of the liga nd (2) and it s dio rgano tin(lV) complexes (8-10) (em) 33
IV
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
ACKNOWLEDGEMENTS
I wo uld like to thank my supervisor Dr Md Abu Affan Resource Chemistry Program
UN IMAS for hi s constant guidance and continuous encouragement without which this work
would no t have been possible I also would like to express my appreciation to Mr Liew Yew
Zion MSc student of Resource Chemistry Program UN IMAS for his occasional help to
complete this report I would like to express my sincere thanks to all staffs of this chemistry
program for their inspiration and valuable ad vice Thank you very much to the Department of
Chemisrty Rajs hahi University Bangladesh for CHN analys is finally I would li ke to express
my grat it ude to my parents brother and sisters who were the constant so urce of inspiration
during the course of this project research work T hanks a lot to all my friends for encouraging
me co nstantly Last but no t least to those who involved d irectly or indirectly in giving hand to
me in completing this project and writing this report though you are unknown by name thank
you very much
Only GOD knows how to reward all of yo u Thank you
II
tgtasal Khldmlll Maklumat AkamIk ~tSrn 11 LHS SAIt~WAJ(
TABLE OF CONTENT Pages
LIST OF TABLES IV
LIST OF FIGURES V
ABSTRACT VI
10 Introduction 11 Coordination compounds of o rganolin(JV) ions 1 2 Objectives
20 Literature Review 2 21 Characterist ic ofN - do no r ligands 2 22 Bidentale nitrogen (NN-) donor ligands 3
23 Trid entate nitrogen (NNN -) donor ligands 5
24 Tetradentate nit rogen (NNNN-) donor ligands 5 25 Chelate Effect 6 26 Organot in(l V) complexes with NN donor ligands 7
30 Materials and Methods 13 3 I General Methods 13 32 Measurement 13 33 Synthes is ofligand (1) and it s orgallotin(JV) complexes (3-7) 14
33 1 Preparatio n of 2-acetylpyridillebenzo phenoneazine [C20 HI )N3] co ntaining NN-donor atoms (1 )
332 Synthesis of [Me2SnCh(C2o H I7NJ)] (3) 333 Synthesis of [Bu2S nClJ(C2HHI)N3)] (4) 33 4 Synthesis of (PhSnC I3(C2oHI )N3) ] (5) 335 Synthesis of(BuSnCI3(C1oH )N3)] (6) 336 Synthesis of[Bu3SnC I(C2oHI7NJ)] (7)
34 Synthes is o f ligand (2) and it s dio rganotin( lV) complexes (8-10) 341 Preparation of 2 -acetylpyridinep henylh yd razo ne [CI1 HI3
dono r atoms (2) 342 Synthesis of(Me2SnCI1(CuHuN3)] (8) 34 3 Synthes is of(Bu2SnCh(CIlHuN3)] (9) 344 Synthesis of [Ph2SnCh(C13 HIJN3)] (10)
40 Results and Discussion 4 1 Phys ical and ana lytica l data
14 15 15 15 15 16 17
3] containing 17 18 18 18
19 2 1
42 Spectroscopic studies of ligands (1-2) and their organotin(lV) corl1p lexes (3-10) 23 42 1 UV-Vis resu lts of ligand (1) and its organot in(lV) complexes (3-7) 23 42 2 IR spectral of liga nd ( 1) and its organotin(IV) complexes (3-7) 26 423 IR spectral 0 f ligand (2) and its organot in(fV) complexes (8-10) 3 I
50 Conclusion 38
60 Suggestion for Future Research 38
70 References 39
11
Pages LIST OF TABLES
Table I Elemental analys is fo r the ligands (1-2) and their organotin(l V) complexes (3-10) 21 Table 2 Mo lar conductance va lues fo r organotin(I V) complexes (3-10) 22 Table 3 The Am (nm) peaks of ligand (I ) and it s organotin(IV) complexes (3-7) 23 Table 4 Main IR data of the liga nd (1) and its o rgano tin(IV) complexes (3-7) (em) 28 Table 5 Ma in IR data of the liga nd (2) and it s dio rgano tin(lV) complexes (8-10) (em) 33
IV
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
tgtasal Khldmlll Maklumat AkamIk ~tSrn 11 LHS SAIt~WAJ(
TABLE OF CONTENT Pages
LIST OF TABLES IV
LIST OF FIGURES V
ABSTRACT VI
10 Introduction 11 Coordination compounds of o rganolin(JV) ions 1 2 Objectives
20 Literature Review 2 21 Characterist ic ofN - do no r ligands 2 22 Bidentale nitrogen (NN-) donor ligands 3
23 Trid entate nitrogen (NNN -) donor ligands 5
24 Tetradentate nit rogen (NNNN-) donor ligands 5 25 Chelate Effect 6 26 Organot in(l V) complexes with NN donor ligands 7
30 Materials and Methods 13 3 I General Methods 13 32 Measurement 13 33 Synthes is ofligand (1) and it s orgallotin(JV) complexes (3-7) 14
33 1 Preparatio n of 2-acetylpyridillebenzo phenoneazine [C20 HI )N3] co ntaining NN-donor atoms (1 )
332 Synthesis of [Me2SnCh(C2o H I7NJ)] (3) 333 Synthesis of [Bu2S nClJ(C2HHI)N3)] (4) 33 4 Synthesis of (PhSnC I3(C2oHI )N3) ] (5) 335 Synthesis of(BuSnCI3(C1oH )N3)] (6) 336 Synthesis of[Bu3SnC I(C2oHI7NJ)] (7)
34 Synthes is o f ligand (2) and it s dio rganotin( lV) complexes (8-10) 341 Preparation of 2 -acetylpyridinep henylh yd razo ne [CI1 HI3
dono r atoms (2) 342 Synthesis of(Me2SnCI1(CuHuN3)] (8) 34 3 Synthes is of(Bu2SnCh(CIlHuN3)] (9) 344 Synthesis of [Ph2SnCh(C13 HIJN3)] (10)
40 Results and Discussion 4 1 Phys ical and ana lytica l data
14 15 15 15 15 16 17
3] containing 17 18 18 18
19 2 1
42 Spectroscopic studies of ligands (1-2) and their organotin(lV) corl1p lexes (3-10) 23 42 1 UV-Vis resu lts of ligand (1) and its organot in(lV) complexes (3-7) 23 42 2 IR spectral of liga nd ( 1) and its organotin(IV) complexes (3-7) 26 423 IR spectral 0 f ligand (2) and its organot in(fV) complexes (8-10) 3 I
50 Conclusion 38
60 Suggestion for Future Research 38
70 References 39
11
Pages LIST OF TABLES
Table I Elemental analys is fo r the ligands (1-2) and their organotin(l V) complexes (3-10) 21 Table 2 Mo lar conductance va lues fo r organotin(I V) complexes (3-10) 22 Table 3 The Am (nm) peaks of ligand (I ) and it s organotin(IV) complexes (3-7) 23 Table 4 Main IR data of the liga nd (1) and its o rgano tin(IV) complexes (3-7) (em) 28 Table 5 Ma in IR data of the liga nd (2) and it s dio rgano tin(lV) complexes (8-10) (em) 33
IV
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Pages LIST OF TABLES
Table I Elemental analys is fo r the ligands (1-2) and their organotin(l V) complexes (3-10) 21 Table 2 Mo lar conductance va lues fo r organotin(I V) complexes (3-10) 22 Table 3 The Am (nm) peaks of ligand (I ) and it s organotin(IV) complexes (3-7) 23 Table 4 Main IR data of the liga nd (1) and its o rgano tin(IV) complexes (3-7) (em) 28 Table 5 Ma in IR data of the liga nd (2) and it s dio rgano tin(lV) complexes (8-10) (em) 33
IV
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
LJST OF FIGURES Pages
Figure I Examples of nitrogen donors with tertiary Sp2-hybridized N atoms 2 Figure 2 22 -bipyrimidine 3 figure 3 23-bis(2-pyridyl)pyrazine 3 Figure 4 [(2-pyridyl-methylene)( phenyl)hydrazinc) 4 Figure 5 66- bis(pirazoloyl)-2 2bipyridin e 4 Figure 6 Pentamethyld iethylenetriamine 5 Figure 7 Nitrophenylethylenediaminediacetic acid 5 Figure 8 Pyridine-2-carbaldehyde azine 6 Figure 9 12 -di(pyridine-2-aldiminoketimino) 6 figure 10 Structure of (a) nicke l hexaamine (b) nickel triethylenediamine and their stability 7 Figure II Dimethyltin(IV) and mono-N-butyltin(lV) trichloride with severa l N- substituted
pyridine-2-carbaldimine 7 Figure 12 SnR2CI2-35-dimethyl-1 -(2 -pyrid yl)pyrazole 8 Figurc 13 Proposed st ructures ofdi-n-butyltin(lV) complexes with pyruvoylamino acid oximes 89 figure 14 Proposed structure of BU2Sn(lV)-2-hydroxyimino-3-phenyl-propionic acid complex 9 Figure IS Proposed (a) MejSn(6-thiopurine) (b) nBu2Sn(6-thio purine)2 and (c) Ph)Sn(6shy
thiopurine) 10 Figure 16 I -methylimidazo le donor I 1 Figure 17 Proposed structures tor organo tin(lV) derivatives of I-dimethylimidazole II Figure 18 [Bis(35-d imethyl-4-( 4 -pyridyl)pyrazole) diphenylt in dichloride 12 Figure 19 UV-vis spectra of li gand ( I) and it s phenyltin(lV) complex (5) 24 Figure 20 UV-vis spectra of ligand ( I ) and it s butyltin(lV) complex (6) 25 Figure21 IRspectrum for ligand [C20 HI 7NJ) ( I) 29 Figure 22 JR spectrum of dimethyltin(lV) complex [(CH3 12S nCh(C~HI7N ) ) ] (3) 30 Figure 23 IR spectrum fo r ligand (CI]H I] )) (2) 34 Figure 24 IR s pectrum of dimet hy ltin(IV) complex [(CH))2SnCI2(CI]H1 ) ))] (8) 35 Figure 25 Proposed structure of the diorgano tin(IV) complexes (3-4) of the ligand (I) 36 Figure 26 Proposed structure of the monoorgano tin(lV) complexes (5-6) of the ligand (1) 36 Figure 27 Proposed structure of the triorganot in(IV) complexes (7) of the Iiganct ( I) 37 Figure 28 Proposed structure of the dio rgano tin(lV) complexes (8-10) of the ligand (2) 37
v
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Coordination Chemistry of Organotin(lV) complexes with NN Donor Ligands
Cynthia anak Paul Sebti
Resource Chemistry Facu lty of Resource Science and Tethnology
Universl ti MalaysIa Sarawak
ABSTRACT
Two ligands have been formed by condensation reaction of 2-acetylpyrid ine with benzophenonehydrazone and phenylhydrazine in 11 molar ratio Organotin(lV) complexes of2shyacetylpyridinebenzophenoneazine and 2-acetylpyrid inephen ylh ydrazo ne have been synthes ized where the ligands are acted as bidentate NN chelating agent The characterization of the ligands (1-2) and their organotin(lV) complexes has been made on the basis of elemental analyses molar conductances UV-vis ible and FTlR spectral studies On the basis of analytical and spectral data octahedral (coordination number six) structures have been proposed
Key words 2-acetylpyrid inebenzophenoneazine 2-acety1pyr id i nep heny Ihydrazo nc o rganotin(lV) complexes spectral studies
ABSTRAK
Dua jenis ligan lelah dihasilkan melalui tindakbalas kondensasi eli onlam 2-aselilpiridina dengan benzoenonhidrazon dan enilhidrazina Kompleks organolin(IV) felah disil1lesis melalui beberapa siri tindakbalas dengan 2-asetilpiridinabenzoenonhidrazon dan 2shyaselilpiridinaenilhidrazina yang berlidak sebagai ligan NN bidenlal Pencirian lerhadap kompleks (3-10) dan ligan (1-2) lelah diakukan dengan menggunakan beberapa kaedah iaitu analisis elemen molar kondukliviti kajian spektra bagi UV-v is dan FTfR Berdasarkan kajian ke alas data analilikal dan spektra maka slnlktur oklahedral (enam nombor koordinasi) lelah dicadangkan
Kala kunci- 2-aseti Ipiridinabenzoen(nazina 2 -asel ilp iridinae n ilh idrazon kompleks organolill(IV) kajian speklra
V I
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
10 Introduction
11 Coordination compounds of organotin(IV) ions
O rganotin(l V) complexes are highly interested areas especiall y for their structural and
biological activities (Mahmood el al 2004) Organotin(lV) complexes with the ligands
containing 0 0- 0 N- and 0 S- donor atoms have investigated by many researchers
Organotin(lV) complexes have been demonstrated to ex hib it relatively hig h ant itumo r activity
as emphasized in recent surveys (Xanthopoulou el al 2003) For complexes [SnR1X2(LL) ]
where LL is an N N- a bidentate nitrogen donor ligand antitumor activity depends on the Sn-N
distances (gt239 A and lt239 A) for the active and inact ive compounds (Alvarez-Boo e ai
2003 Xanthopou lou el ai 2003 Chojnacki el ai 2001) respectively which suggests that
dissoc iat ion of the ligand is a s ignificant step in their mechanism Due to such a wide range of
app lications new o rganot in(IV) with different types of NN- donor ligands are of particular
interest The present project research has reported the preparation and characterization of several
organotin( I V) complexes with the NN- donor ligands namely 2shy
acetylpyr idinebenzophenoneazine ligand (1) and 2-acetylpyridinepheny lhydrazo ne ligand (2)
12 Objectives
The objectives of this study are
I To synthes ize NN- donor ligands
II To synthesize organotin(lV) complexes with NN- donor ligand s
III To characterize NN - donor liga nds and their organotin(fV) complexes using molar
conductances CHN analyses liV-visible and FT-I R spectral studies
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
20 Literature Review
21 Characteristic ofN- donor ligands
N it rogen dono r ligands have great in fl uence upo n coord ination chemis try e nvironment
Nit rogen do nor ligands are class ified into 3 gro ups that are Sp3 Sp2 and sp T his class ifi cation is
based on hybridization ofN atom
The example of Spl -hybrid ized nitrogen do no r atoms is trimethy lamine N-H bonds are
always unsuitable fo r organo metallic reactio n The H atom presence make the environment
become ac idic
Any ligands that contain sp2-hyb ridized nitrogen atoms especially N atom is a part of
aro matic system has big potentia l coo rdination chemistry This kind o f ligands is mo re
fu nctional coo rdinat io n chemistry if they are bidentate or tetradent ate
T hese are so me example o f the nitrogen do nor ligands that has been synthesized by
prev io us researchers
~-~NII~ ~Jo ~
N
~
N
N ~
Figure 1 Examples ofnit rogcn donors with tertiary sp2-hyb ridized N atoms
shyN
2
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
The presence of C=N and C= C double bond s in several mol ecu les in Figure I can make
them easily to experience furt her reaction such as nucleophilic attack and hydrogenation The
organic nitrogen dono r with sp hybridizat io n is nitriles group T his group acts as lab ile ligand s
which mean they could be rep laced by appropriate reagents Nitril es are qu ite lab ile towards
nucleophilic attack once coordinated
22 Bidentate nitrogen (NN-) donor ligands
NN- donor ligand is a co mpound has two N atoms that are able to bond with any central
metal cation Some common examp les of this kind of ligand are ethy lened iamine(en) and
dipyridine
Shava leev el ai (2002) have reported the synthesis o f bidentate 22-b ipyr imidine a nd 2
3-bis(2-pyrid yl) as new NN- donor ligand (Figure 2-3) Both of ligands act as bidentate nitrogen
donor ligand via externa l vacant NN - donor diimine type binding sit es
Figure 2 22 -b ipyrim id ine
_NN_
Figure 3 23-bis(2-pyrid yl)pyraz ine
3
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Another example o f NN - dono r ligand [(2 -pyrid yl-methylene)(phenyl)hydrazineJ
reported by Tarafder el al (2003) The structure of [(2-pyridyl-meth ylene)(phenyl)hyd razineJ is
shown in Figure 4 This ligand [(2-pyridyl- methylene)(phenyl)hydrazineJ also acted as bidentate
NN - nit rogen donor ligand and iso lated ITo m the condensation o f pyridin e-2-ca rboxaldehyde
with phenylhydrazine in ethano l
Figure 4 [(2-pyrid yl-methylene)( phenyl)hydrazineJ
Recentl y 66 -bis(pirazo lyl)-22 bipyridine o ne type o f NN - dono r liga nd which is
obtained by Kowalczyk and Skarzewski (2005) which acts as chiral NN bide ntate donor ligands
Mo lecular structure is sho wn in Figure 5
Me ~Me MeO~ ~
Ph N_NT(Ny
C CI NiCI2(Ph3P)2 Ph3P Zn
DMF
(a)
(b)
(a) 2-ehloro-6-[3-( l-methoxy-l-phenyl- eth yl)-5-methylpyrazo l-l-yIJpyr id ine (b) 66 -bis(pirazo ly l)-22 -bipyridine
Figure 5 66- bis(pirazo lyl) -22 bipyridine
4
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Kbillmal MakJumal Ak~mik 1T(Vf5-1 t v ~ v WAK
23 T ridentate nitrogen (NNN-) donor ligands
One of the most commo n tridentate nitrogen donor ligand IS
pen ta methyld iethy lenetria m in e has been reported by Patel el al (2004)
Pentamethyldiethylenetriamine is a tridentate nitrogen donor ligand with donor groups suitably
placed for forming two 5-membered chelate ring Pentamethyldiethylenetriamine also acts as
superoxide scavenging ability The donor ligand mo lecular structure can be seen in Figure 6
Figure 6 Pentamethyldiethylenetriamine
Another type of tridentate nitrogen donor ligand (NNN-) IS
nitrophenylethylenediaminediacetic acid (Figure 7) has been reported by Allah er at (2004)
Nitrophenylet hylenediaminediacet ic ac id acts as tridentate ligands (via the two ac ids and the
tertiary amine function s)
Figure 7 N it rophenylethylenediamined iacet ic acid
24 Tetradentate nitrogen (NNNN-) donor ligands
One ofthe NNNN- donor ligand having a pyridyJ back bone is synthes ized by Toupance
el ([I (2002) It is pyridine-2-carbaldehyde azine that is shown in Figure 8 Pyridine-2shy
carbaldehyde azine act as tetradentate nitrogen dono r ligand v ia its nitrogen atom
5
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Figure 8 Pyridine-2-carbaldehyde azine
Kulshreshtha and his co workers (1989) reported the synthesis of new tetradentate
nitrogen donor ligands 12-di(pyridine-2-aldiminoketimino) They were derived from the
condensation reaction of pyridine 2-carboxyaldehyde or 2-acetylpyridine with ethylenediamine
and propylenediamine and refluxing condition in ethanol The ligand structure is shown in
Figure 9
R R
+ NH (CHC H )nNH bull -N-(CH 2)n-N + 2 H2o( o-L) N
N ~ =----shy
Figure 9 12 -di(pyridine-2-aldiminoketimino) where R= HCH) n = 23
25 Chelate Effect
Chelate means any ligand that has capability bo nded with any central metal atom through
more than one donor ato m This chelate effect can be seen c learly by comparing the multidentate
ligand complexes and mo nodentate ligand co mplexes In fact the multidentate ligand complexes
are more stab le compare to monodentate ligand complexes From the example
has chelate effect since the the ligand coordinated via more than one nitrogen atom of the ligand
Whereas [Ni(NH))6l 2 + form the complex with monodentate nitrogen atom See the example as
tollow
6
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
2+
2 6I I - (q) + log B= 86
(a) Nickel hexaamine
2+
Ni ~ f- 3H1NCH1CH1NH2(aq)
log B= 18 3
(b) Nickel triethylenediamine
stability
26 Organotin(V) complexes with NNINNN donor ligands
Tanaka el of (1979) ha ve synthes ized 11 mo lecular add ucts of dimethyltin(IV) and
mono -N-butyltin(lV) trichloride with seve ral N- substituted pyridine-2-carbaldimine (Figure
1 I )
n=1 R=n-butyl n=2 R=Me R= Me 4-MeC6 H 4
Figure II Dimethyltin(IV) and mono-N -butyltin(lV) trichlo ride with several N- substituted pyridine-2-carbaldimine
7
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
When the substituent R on the imine nit rogen atom is Me Et or CH1Ph the adduct exist
as a mixture of two iso mers in aceton itrile on the basis of I H chemica l shifts of the ligand
protons and their spin-spin coupling constants wit h the tin nuclei
Alvarez-Boo and hi s co-workers (2003) have synthes ized SnR1CI1-3 5-dimethyl-l-(2shy
pyridyl)pyrazo Ie
R=Me n Bu Ph etc
Figure 12 SnR1Cb-35-dimethyl-I-(2 -pyridy l)pyrazo le
Szorcsik and his co-workers (2003) have synthesized I 1 mo lecular adducts of
pyruvoylamino acid oximes with 8u)SnO that is shown in Figure 13
(a)
8
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
H~ CH3
BU I N= C
tC
in-N =0
Bu I o CH-R
~C II o
(b)
Figure 13 Proposed structures of di-n-butyltin(lV) complexes with pyruvoylamino acid oximes
The organotin(IV) moieties react with the carboxylate [OJ and peptide and oxime [N]
ato ms of the ligands is clearly seen by using FT-IR and Raman spect ra (Szorcsik el al 2003)
Found that in the most cases the -COO- group monodentately coord inated to the central atom
and most of the complexes probably have monomeric structures (Szorcsik et at 2003)
Figure 14 Proposed structure of BuS n(V)-2-hydro xy imino-3-p he nyl- prop ionic acid complex
Zhang and his co workers (2004) have synthesized triphenyl(6-thiopurin yl)tin and
in vestigated the structure using X-ray diffi-action
9
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
(a)
s
t~)N N
Ph~1 Sn-Ph
Ph I N N
ltNJ S
(e)
Figure 15 Proposed (a) Me3Sn(6-thiopurine) (b) nBu2S n(6-thiopurineh and (e) Ph3Sn(6-thiopurine)
10
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Organotin(IV) complexes containing mono or bidentate N- donor ligands as 1shy
methylimidazo le derivatives have been reported by Pettinari el of ( 1998)
HC-N II
HC CH N I CH3
Figure 16 I-methylimidawle donor
R=Me Et Bun or Ph n=1 2 3
(a)
Z= X or R R= Me Et Bun Ph n= 1 2 3 X= CI Br I
(b)
Figure 17 Proposed structures for organotin(IV) derivatives o f 1shydimeth ylimidazole
11
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Recently Cui and his co-workers (2005) have been studied the donating ability of ligand
35-dimethyl-4-(4-pyridyl)pyrazole with organotin(lV) chloride(s) They found that nitrogen
atom ofpyridyl exhibits stronger donating ability compare to nitrogen atom in the pyrazole ring
toward tin atom The [bis(3S-dimethyl-4-(4-pyridyl)pyrazole] diphenyltin dichloride structure
is shown in Figure 18
~
~ CI IQN---- - NH
N-Sn--N H~ II ---=Nilt l I
Figure 18 [Bis(3 S-dimethyl-4-( 4 -pyridyl)pyrazole] diphenyltin dichloride
From the literature reviews studies on organotin(lV) complexes of corresponding NN-
donor ligands are less studied (Alvarez-Boo el aI 2003 Matsubayashi el aI 1971) Therefore
the author has undertaken this project for the purpose of synthesizing and characterizing
organotin(IV) complexes with NN- donor ligands
12
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
30 Materials and M~thods
31 General Methods
All chemicals were obtained from Fluka Aldrich and JT Baker All solvents were
distilled base on the published methods by Armarego before used (Almarego and Perrin 1996)
All solvents were distilled and dried before used as follows methanolethano l purified and dried
from distillation with magnes ium turning and iodine and dry benzenehexane is obtained by
distilling w ith sod ium and sma ll amo unt of benzophenone and purified und er nitrogen from
sodium benzophenone ketyl
All the purifi ed and dried so lvents were kept in molecular sieves All the reactions were
conducted under dry nitrogen atmosp here using Schlenk Vacuum Line techniques
32 Measurement
Bidentate nitrogen donor ligands and their organotin(IV) complexes were characterized by
elemental and spectra l anal yses E lemental analyses are CHN analyses and mo lar condu ctance
analyses The spectral studies are UV-vis ible and FTIR spectra studies Organotin(lV) halide(s)
complexes were preserved in freezer for long-term storage and stability
The IR spectra were recorded as KEr disc using Perkin Elmer Spectrum OX Fouriershy
Transform Spectrometer (4000-400 ern) at UNIMAS Electronic spectra werc recorded with
benzene as a solvent on a Perkin Elmer Lambda 2S UV-Visible spectrometer at UNIMAS The
concentration is I xlO-4 M Molar conductances were measured at room temperature using Hanna
EC 215 Conductivity Meter at UNlMAS and using methanol as so lvent
13
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
33 Synthesis of ligand (1) and its organotin(lV) complexes (3-7)
331 Preparation of 2-acetylpyridinebenzophenoneazine ICzoHI7N3] containing NN- donor
atoms (1)
A solution of 2-acetylpyridine (0486 g 0004 mole) in an absolute ethanol (20 rnL) was
added to a solution of benzophenonehydrazone (0784 g 0004 mole) in absolute ethanol (20
mL) The mixture was heated to reflux for 4-5 hours under nitrogen atmosphere with stirring
The color of the solution was changed from pale yellow to yellow The mixture was let in the
refrigerator for overnight and the required product precipitated out as white micro crystals The
yellow solid was filtered off and washed with pentane The residue was recrystallized from
pentane Yield 0560 g 4409 mp 108-110 0c
Schematically the reaction between 2-acetylpyridine and benzophenonehydrazone to form
2-acetylpyridinebenzophenoneazine and water produced during condensation reaction as by-
product showed as below
~CH H N2 absolute ethanol N
N-N_ H O+ bull N + 2OyCH H IStirredrefluxed for 5-6 hours o --- ~
I 1 ~-
(a) (b) (c)
Where a 2-acetylpyridine b benzophenonehydrazonc c 2shyacetylpyridinebenzophenoneazine
14
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
Synthesis of organotin(lV) complexes with NN- donor ligand (1)
332 Synthesis of IMelSnCIl(CloHI7NJ)] (3)
Ligand (1) (0299 g 0001 mole) was suspended in hexane (20 mL) and warmed s lowly to
give a palc ydlow so lution This was then slowly added to a suspens ion ofMe2SnCb (0219 g
0001 mole) in hexane (20 mL) with constant stirring under nitrogen atmosphere The color of
the mixture was changed from pale yellow to yellow The solution mixture was refluxed for 3-4
hours aft er which a whit e precipitation was obtained The mi xture was allowed to coo l and
filtered off The white precipitate was washed with hexane and dried in vacuum des icato r Yield
03 89 g 7509 mp 135- 138 dc
333 Synthesis of [BulSnClz(CzoHI7NJ)] (4)
This dibutyltin(IV) comp lex (4) was prepared by applying similar method as described tor
synthes izing complex (3) by replacing Me2SnCb with BU2SnCb (0310 g 0001 mole) The
white precipitate was washed with hexane and dried in vacuo over sili ca ge l Yield 0389 g
7754 mp 120-122 DC
334 Synthesis of ]PhSnCb(C20H 17NJ)] (5)
This phenyltin(IV) complex (5) was prepared by applying the same methods as for
synthes izing complex (3) by replac ing Me2SnCI2 with PhSnCb (0300 g 0001 mole) The white
precipitate was was hed with hexane and dried in vac uo over silica gel Yie ld 0585 K 9750
mp 162-165 DC
335 Synthesis of [BuSnCi3(CzoH 17NJ)] (6)
This butyltin(lV) complex (6) was prepared by using similar procedures as described for
synthesizing complex (3) by replacing Me2SnCb with BuSnCI) (0281 g 000 1 mole) The white
15
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16
precipitate was washed with hexane and dried in vacuo over silica gel Yield 0554 g 9551
mp 138-141 dc
336 Synthesis of [BuJ SnCl(CzoH 17 N))1 (7)
This tributyitin(lV) complex (7) was prepared by using similar method as a applied for
synthesizing compl ex (3) by replacing MelSnCh with Bu)SnCI (0325 g 000 ] mole) The white
precipitate was washed w ith hexane and dried in vacuo over s ili ca geL Yield 0552g 8850
mp91-94 degC
16