1
Synthetic approach towards ‘Click’ modified chalcone based organotriethoxysilanes; UV–Vis study
Gurjaspreet Singh,* Jandeep Singh, Satinderpal Singh Mangat, Aanchal Arora
Department of Chemistry and Centre of Advanced Studies, Panjab University, Chandigarh, 160014, India.
*Corresponding Author
Email: [email protected], Phone: +91-0172-2534428
Electronic Supplementary Material (ESI) for RSC Advances.This journal is © The Royal Society of Chemistry 2014
2
1. General reaction procedure
2. NMR (1H, 13C), uv-vis spectra of silane 4a
3. NMR (1H, 13C), of silane 4b
4. NMR (1H, 13C), uv-vis spectra and MS of silane 4c
5. NMR (1H, 13C), uv-vis spectra of silane 4d
6. NMR (1H, 13C), uv-vis spectra of silane 4e
7. NMR (1H, 13C), uv-vis spectra and HRMS of silane 4f
8. NMR (1H, 13C), uv-vis spectra of silane 4g
9. NMR (1H, 13C), uv-vis spectra of silane 4h
10. NMR (1H, 13C), uv-vis spectra and HRMS of silane 4i
11. NMR (1H, 13C), uv-vis spectra of silane 6a
12. NMR (1H, 13C), uv-vis spectra of silane 6b
13. NMR (1H, 13C) and MS of silane 6c
14. NMR (1H, 13C), uv-vis spectra of silane 6d
15. NMR (1H, 13C), uv-vis spectra of silane 6e
16. NMR (1H, 13C), uv-vis spectra of silane 6f
4–5
6–8
9–10
11–14
15–17
18–20
21–24
25–27
28–30
31–34
35–37
38–40
41–43
44–46
47–49
50–52
3
17. NMR (1H, 13C), uv-vis spectra of silane 6g
18. NMR (1H, 13C), uv-vis spectra of silane 6h
19. NMR (1H, 13C), uv-vis spectra of silane 6i
53–55
56–58
59–61
4
Experimental
Caution! Azide compounds are explosive to heat and shock. Great care and protection is required for handling of these compounds.
5.1. General material and methods: All the syntheses were carried out under dry nitrogen atmosphere using vacuum glass line. The organic
solvents used were dried and purified according to the standard procedure and stored under dry nitrogen atmosphere.
bromotris(triphenylphosphine)copper(I) (Aldrich), γ-chloropropyltriethoxysilane (ClPTES) (Aldrich), propargyl bromide (80% wt. solution in
toluene) (Aldrich), sodium azide (SDFCL), potassium carbonate (THOMAS BAKER), N,N-dimethylformamide (SDFCL), were used as
supplied. Acetophenone (SDFCL), 2-hydroxyacetophenone (SDFCL), 3-hydroxyacetophenone (SDFCL), 4-hydroxyacetophenone (SDFCL),
salicylaldehyde (Aldrich), 3-hydroxybenzaldehyde (SDFCL), 4-hydroxybenzaldehyde (SDFCL), p-methoxyacetophenone (HIMEDIA), 2,4-
dimethoxyacetophenone (HIMEDIA) were used as supplied for synthesis of terminal alkynes 3a–3i and 5a–5i.
Infrared spectrum was obtained neat on a Thermo Scientific Fischer spectrometer. Multinuclear NMR (1H, 13C) spectra were recorded on a
Bruker advance II 400 spectrometer (in CDCl3) at 25 °C. HRMS data of all synthesized compounds 4a–4i and 6a–6i was recorded on Waters
QQ–TOF micro Mass Spectrometer. UV–Vis spectra were recorded on JASCO V–530 UV–Vis spectrophotometer. The elemental data were
obtained on Thermo Scientific flash 2000 organic elemental analyzer.
AzPTES was synthesized according to known procedure in literature.20
Synthesis of compounds 2a(i–iii) and 2b(i–iii)
To a uniformly stirred solution of 1a/1b (2g, 16.40 mmol, 1 equiv) in 15 ml of DMF cooled in ice bath, added K2CO3 (6.76 g, 47.2 mmol, 3
equiv) and propargyl bromide (2.15 g, 1.61 ml, 18.06 mmol, 1.1 equiv) dropwise within 5 min. After complete addition of reactants, the
temperature of reaction mixture was slowly raised to 30 ℃ and stirred for 14 h. The reaction was then quenched by addition of ice cold water
and filtered the solid product (in case of 2a(i, iii); 2b(i–iii)). In case of low melting solids 2a(ii), extraction was carried out with ethyl acetate.
5
The combined organic layers were dried over anhydrous MgSO4 and vacuum evaporation of solvent resulted into the formation of desired
compound. The solid alkynes were recrystallized by dissolving in minimum amount of ethanol.
Synthesis of compounds 3a–3i/5a–5i
To a uniformly stirred solution of 2a (1 equiv) and KOH (0.02 g, 0.36 mmol) in 15 ml of ethanol, ethanolic solution of substituted acetophenone
1c(a–c) or 2b (1 equiv) was added slowly within 10 min. The reaction was stirred for 4 h and monitored the end point using TLC (hexane:ethyl
acetate (8:2)). On completion, the reaction was quenched by ice cold water, extracted with methylene chloride and washed twice with brine
solution. The combined organic phases were dried over anhydrous MgSO4 and vacuum evaporation afforded the desired product.
Synthesis of compounds 4a–4i/6a–6i
In a 25 ml two neck round bottom flask, to stirred solution of alkyne 3a–3i/5a–5i in 1:1 solution of THF:TEA (3ml), added AzPTES (1 equiv for
3a–3i and 2 equiv for 5a–5i) followed by catalyst (0.02 mmol for 3a–3i and 0.04 mmol for 5a–5i) loading under inert atmosphere. Slowly the
temperature of reaction mixture was raised to 65 ℃ and stirred vigorously for 3 h. After completion of reaction, it was cooled to room
temperature, filtered and vacuum evaporation of solvent resulted in desired nPTES 4a–4i/6a–6i.
6
4a
7
8
250 275 300 325 350 375 400-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
4a
Abso
rban
ce
Wavelength (nm)
9
4b
10
11
4c
12
13
WATERS, Q-TOF MICROMASS (LC-MS) SAIF/CIL,PANJAB UNIVERSITY,CHANDIGARH
m/z80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400 420 440 460 480 500 520 540 560
%
0
100JANDEEP 4b 20 (0.251) Cm (10:30) TOF MS ES+
7.30e3532.37299
430.31819
301.11059102.2
900279.2611
393.3692362.2
490347.2488331.2
273
464.31171
431.3358 450.3
223
465.3332
533.32066
534.3403
14
250 300 350 400-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
4c
Abso
rban
ce
Wavelength (nm)
15
4d
16
17
250 275 300 325 350 375 400
0.0
0.5
1.0
1.5
2.0
2.5 4d
Abso
rban
ce
Wavelength (nm)
18
4e
19
20
250 275 300 325 350 375
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0 4e
Abso
rban
ce
Wavelength (nm)
21
4f
22
23
WATERS, Q-TOF MICROMASS (LC-MS) SAIF/CIL,PANJAB UNIVERSITY,CHANDIGARH
m/z50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 450 475 500 525 550 575 600 625 650 675 700 725 750 775
%
0
100JANDEEP 4f 21 (0.303) AM (Top,4, Ar,5000.0,556.28,0.70,LS 10); Sm (Mn, 2x3.00); Sb (1,40.00 ); Cm (21:24) 1: TOF MS ES+
8.84e3562.22888843
494.20714839430.1759
4616
362.14944118
279.09411998
84.9628904 206.5573
701125.9861
680176.1075
467
232.5817339
289.60181547
359.2391337
363.15001065
412.1662289
431.1855872
432.1760238
495.21351327
559.23371099
496.2099340
611.32205189
563.23272557
564.2375535
612.34481684
624.2109765
625.2200243 698.2740
160763.3534
130785.3771
57
24
250 275 300 325 350 375 400
0.0
0.5
1.0
1.5
2.0
2.5
3.04f
Abso
rban
ce
Wavelength (nm)
25
4g
26
27
250 275 300 325 350-1.5
-1.0
-0.5
0.0
0.5
1.0 4g
Abso
rban
ce
Wavelength (nm)
28
4h
29
30
250 275 300 325 350 375 400 425 450-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
4h
Abso
rban
ce (n
m)
Wavelength
31
4i
32
33
WATERS, Q-TOF MICROMASS (LC-MS) SAIF/CIL,PANJAB UNIVERSITY,CHANDIGARH
m/z75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 450 475 500 525 550 575 600 625 650 675 700 725 750 775 800
%
0
100JANDEEP 4i 16 (0.218) AM (Top,4, Ar,5000.0,556.28,0.70,LS 10); Sm (Mn, 2x3.00); Sb (1,40.00 ); Cm (16) 1: TOF MS ES+
4.79e3592.23654789
570.25863084
301.0778470
279.0841449102.1311
431
181.092371
103.131522
242.135160
524.2245213302.0746
62 443.645955
343.192030
422.218917
466.15975
593.25501590
594.2508272
671.396890608.2305;89 728.2656
43789.3711
24
34
250 275 300 325 350 375 400-0.8
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4 4i
Wav
elen
gth
(nm
)
Absorbance
35
6a
36
37
250 275 300 325 350 375 4000.0
0.5
1.0
1.5
2.0
6a
Abso
rban
ce
Wavelength (nm)
38
6b
39
40
250 275 300 325 350 375 400
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
6b
Abso
rban
ce
Wavelength (nm)
41
6c
42
43
WATERS, Q-TOF MICROMASS (LC-MS) SAIF/CIL,PANJAB UNIVERSITY,CHANDIGARH
m/z100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000
%
0
100JANDEEP 6b 23 (0.288) Cm (7:30) TOF MS ES+
6.47e3833.56470
811.62243
444.31196
301.1661102.2
444279.1423
425.3628
586.41178
564.4484445.3
261 475.4201
765.5599587.4
373632.4195 766.5
264
834.52665
835.6718
879.6486
880.6;229
44
6d
45
46
250 275 300 325 350 375 4000.0
0.5
1.0
1.5
2.0
2.5 6d
Abso
rban
ce
Wavelength (nm)
47
6e
48
49
250 275 300 325 350 375 4000.0
0.5
1.0
1.5
2.06e
Abso
rban
ce
Wavelength (nm)
50
6f
51
52
250 275 300 325 350 375 400-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
6f
Abso
rban
ce
Wavelength (nm)
53
6g
54
55
250 275 300 325 350 375 4000.0
0.2
0.4
0.6
0.8
1.0
1.2
1.46g
Abso
rban
ce
Wavelength (nm)
56
6h
57
58
250 275 300 325 350 375 4000.0
0.2
0.4
0.6
0.8
1.0
1.2 6h
Abso
rban
ce
Wavelength (nm)
59
6i
60
61
250 275 300 325 350 375 4000.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
6i
Abso
rban
ce
Wavelength (nm)