1. 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

2. 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.ppthttp://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 said and 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

3. T(NMR), Tcorr 132, 125 125, 118 120, 113 118, 111 „tertiary carbon“ T(NMR), Tcorr 165, 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.pxphttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay0,Gr0 / Lay1,Gr1 CH3´s ppm

4. T(NMR), Tcorr 132, 125 125, 118 120, 113 118, 111 C2,C6 T(NMR),Tcorr 165,154 152,143 140,132 139,131 132,125 https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxphttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay0,Gr0 / Lay2,Gr2 „tertiary carbon“ C2,C6 CH3´s ppm

5. T(NMR), Tcorr 132, 125 125, 118 120, 113 118, 111 CH3´s T(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.pxphttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay0,Gr0 / Lay3,Gr3 „tertiary carbon“ C2,C6 CH3´s ppm

6. D = 0.046 ppm CH3´s D = 0.046 ppm „tertiary carbon“ ppm https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxphttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay3,Gr3 / Lay1,Gr1 „tertiary carbon“ T(NMR), Tcorr 165, 154 152, 143 140, 132 139, 131 132, 125 125, 118 CH3´s T(NMR),Tcorr 179, 167 165,154 152,143 140,132 139,131 132,125 125, 118

7.  = 0.044 ppm C2,C6 ppm https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxphttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay2,Gr2 C2,C6 T(NMR),Tcorr 165,154 152,143 140,132 139,131 132,125

8. TNMR [K]zTcorr [K] 117,0-1,505109,9 118,0-1,486111,0 120,0-1,448113,1 125,0-1,354118,2 132,0-1,222125,0 139,0-1,090131,4 140,0-1,071132,2 152,0-0,844142,8 165,0-0,599154,2 179,0-0,335166,9 https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls

9. 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):

10. Geometries:B3LYP-D3BJFrom Ragnar: PBE1PBE NMR calculationsTMS NMR basis:Shielding186,4997ppm aug-pcS-2 on C def2-TZVP on Si and H axeq No.ShieldingChemical shiftNo.ShieldingChemical shiftDifference 1152,366134,13361152,155734,3440,2104 2156,910229,58952156,581429,91830,3288 3175,44411,05573175,331811,16790,1122 5175,472411,02735175,33211,16770,1404 6156,88929,61076156,581129,91860,3079 18163,801322,698418165,53920,9607-1,7377 19155,300531,199219156,936429,5633-1,6359 23156,210730,28923156,935729,564-0,725 27156,226830,272927158,427228,0725-2,2004 TBu-Me- Average155,91266730,5870333 TBu-Me- Average157,433129,0666-1,5204333 https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140416.xlsx

11. It looks as if the observed  (ax-eq) values are a lot smaller than the predicted values

12. 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

13. Splitting (ax-eq (?)) is seen in all 13 C 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 ppm CH 3 ´s6.3 Hz; 0.063 ppm C2,C6:5.7 Hz; 0.057 ppm C3,C5:5.9 Hz; 0.059 ppm C4:6.5 Hz; 0.065 ppm -this contradicts Ragnars chemical shift calculations(?!) https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls

14. T(NMR)=132/Tcorr=125K C4…… C3,C5 C2,C6 tBu-C CH 3 ´s https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxphttps://notendur.hi.is/agust/rannsoknir/SCH/Jan14/PXP-140415.pxp; Lay4,Gr5  /Hz Calc. Exp.  (e-a) %e kab+kba Hzs -1 6.53818 5.94014 5.73913 5.2389 6.34018 https://notendur.hi.is/agust/rannsoknir/SCH/Jan14/XLS-140415.xls