SCH-tBu; working procedure; update: 140419

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PPT-140415.pptx

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140416.xlsx

Mynd: https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140416.xlsx

I. MESTRE-C procedure for creating NMR spectra from Fid´s according to http://www3.hi.is/~agust/kennsla/ee10/ees10/PPT/ees-DNMR-10.ppt :

„nuts files (necessary input files for WINDNMR) are created with Mestre C as (inside Mestre C):File->import spectra->....schsih3-> FID gogn->Select for example sow417mr.163->open->FT -> 256K->Apply along t1->Phase correction(if needed):select region of interest by using magnifying glass(+) and click and drag untill satisfactory-> press phase correction button->click mouse as saidand hold and drag up or down and you will see the phase change; stop when it is good->OK->File->Export file -> nuts->...appropriate file-> type name: schsih3-163.nts->save

80

60

40

20

0

-20

30 25 20 15 10 5

200

150

100

50

0

17.0 16.8 16.6 16.4 16.2

T(NMR), Tcorr132, 125

125, 118

120, 113

118, 111

„tertiary carbon“T(NMR), Tcorr165, 154

152, 143

140, 132

139, 131

132, 125

125, 118

„tertiary carbon“

C2,C6

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay0,Gr0 / Lay1,Gr1

CH3´s

ppm

80

60

40

20

0

-20

30 25 20 15 10 5

T(NMR), Tcorr132, 125

125, 118

120, 113

118, 111

400

300

200

100

0

8.4 8.2 8.0 7.8 7.6

C2,C6T(NMR),Tcorr165,154

152,143

140,132139,131

132,125

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay0,Gr0 / Lay2,Gr2

„tertiary carbon“

C2,C6

CH3´s

ppm

800

600

400

200

0

27.6 27.4 27.2 27.0 26.8 26.6 26.4

80

60

40

20

0

-20

30 25 20 15 10 5

T(NMR), Tcorr132, 125

125, 118

120, 113

118, 111

CH3´sT(NMR),Tcorr

179, 167

165,154

152,143

140,132

139,131

132,125

125, 118

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay0,Gr0 / Lay3,Gr3

„tertiary carbon“

C2,C6

CH3´s

ppm

800

600

400

200

0

27.0 26.9 26.8 26.7 26.6

D = 0.046 ppm

CH3´s

200

150

100

50

0

16.8 16.7 16.6 16.5 16.4

D = 0.046 ppm

„tertiary carbon“

ppm ppmhttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay3,Gr3 / Lay1,Gr1

„tertiary carbon“T(NMR), Tcorr165, 154

152, 143

140, 132

139, 131

132, 125

125, 118

CH3´sT(NMR),Tcorr

179, 167

165,154

152,143

140,132

139,131

132,125

125, 118

500

400

300

200

100

0

8.05 8.00 7.95 7.90 7.85 7.80

D = 0.044 ppm

C2,C6

ppmhttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay2,Gr2

C2,C6T(NMR),Tcorr165,154

152,143

140,132139,131

132,125

TNMR [K] z Tcorr [K]

117,0 -1,505 109,9

118,0 -1,486 111,0

120,0 -1,448 113,1

125,0 -1,354 118,2

132,0 -1,222 125,0

139,0 -1,090 131,4

140,0 -1,071 132,2

152,0 -0,844 142,8

165,0 -0,599 154,2

179,0 -0,335 166,9

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls

http://skemman.is/en/stream/get/1946/13944/33497/1/master.pdf

Úr MS-ritgerð Nönnu R. Jónsdóttur, p:32 (NB: toppum hefur verið hliðrað):

Geometries:B3LYP-D3BJ From Ragnar:

PBE1PBE NMR calculations TMSNMR basis: Shielding 186,4997ppmaug-pcS-2 on Cdef2-TZVP on Si and H

ax eqNo. Shielding Chemical shift No. Shielding Chemical shift Difference

1 152,3661 34,1336 1 152,1557 34,344 0,21042 156,9102 29,5895 2 156,5814 29,9183 0,32883 175,444 11,0557 3 175,3318 11,1679 0,11225 175,4724 11,0273 5 175,332 11,1677 0,14046 156,889 29,6107 6 156,5811 29,9186 0,3079

18 163,8013 22,6984 18 165,539 20,9607 -1,7377

19 155,3005 31,1992 19 156,9364 29,5633 -1,635923 156,2107 30,289 23 156,9357 29,564 -0,72527 156,2268 30,2729 27 158,4272 28,0725 -2,2004

TBu-Me-Average 155,912667 30,5870333

TBu-Me-Average 157,4331 29,0666 -1,5204333

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140416.xlsx

• It looks as if the observed Dd(ax-eq) values are a lot smaller than the predicted values

Need to download WinDNMR according to:

http://www.chem.wisc.edu/areas/reich/plt/windnmr.htm

NB: Use password given in 2009

It is working OK

Splitting (ax-eq (?)) is seen in all 13C signals (tBu-C, the CH3´s, C2/C6, C3/C5 and C4) for T(NMR) = 132 (Tcorr=125 K);the splitting being only slightly different in magnitude:

tBu-C: 5.2 Hz; 0.052 ppmCH3´s 6.3 Hz; 0.063 ppmC2,C6: 5.7 Hz; 0.057 ppmC3,C5: 5.9 Hz; 0.059 ppmC4: 6.5 Hz; 0.065 ppm

-this contradicts Ragnars chemical shift calculations(?!)

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls

-120-100-80-60-40-2002040

T(NMR)=132/Tcorr=125K

C4……

C3,C5

C2,C6

tBu-C

CH3´s

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay4,Gr5

Dn/Hz

Calc.Exp. D(e-a) %e kab+kbaHz s-1

6.5 38 18

5.9 40 14

5.7 39 13

5.2 38 9

6.3 40 18<39> <14.4>

https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls