SCH-Br Summary of spectra vs T, (slides: 3-7 (“hot”); 10-11(“cold”)) calc. vs. exp. chemical shift differences for ax.-eq. (C2-C6, C3-C5, C4) (slides 11) DNMR-analysis for C3-C5 (slides: 12-14) PPT´s: IGOR´s: XLS´s : Si Br H Si Br H

nuts and txt- TNMR [K]zTcorr [K]file namesi:size/K SCH-Br ib b b b b b b b b b b b64 highb64

TNMR [K]Tcorr [K] high C4 C3,C5 C2,C6 ppm SCH-Br

TNMR [K]Tcorr [K] high C2,C6 ppm SCH-Br

TNMR [K]Tcorr [K] high ppm SCH-Br C3,C5 eq. ax. X X

TNMR [K]Tcorr [K] high ppm SCH-Br C4

Calc, ax.-eq = C4 C3,C5 C2,C6 SCH-Br ppm

Comments: Chemical shift calculations seem to overestimate abs(ax.-eq.) spacings for C2/C6 & C3/C5 Not clear what is the case for C4 Only possible to determne chemical shift for eq. For C3,C5 Further cooling needed to determine chemical shifts for eq. For C2,C6 and C4 New “colder” spectra added:

ppm TNMR [K]Tcorr [K] high C4 C3,C5C2,C6 SCH-Br TNMR [K]Tcorr [K]

Layout:0, Gr:0 ppm C4 C3,C5C2,C6 SCH-Br TNMR [K]Tcorr [K] eq

ppm C4 C3,C5C2,C6 SCH-Br eq ax.-eq = Calc. Exp. TNMR [K]Tcorr [K] ppm ppm

parametervalueunit R8.315J K-1 mol K K(eq->ax) %a(e) (low field; Cl eq)14.3 %b(a) (high field: Cl3 ax)85.7 DG(eq->ax) J mol-1 DG(eq->ax) kJ mol-1 DG(eq->ax) kcal mol-1 conversion factor0.239kcal/kJ kB1.381E-23J K-1 h6.626E-34J s R8.315J K-1 mol-1 Si Br Si Br ax eq G G#G# (eq->#; see below)

kcal mol-1 DG#(eq->#) Tc ksum k(eq->ax)k(ax->eq) T corr G#G#  G # =  H # -T  S # =>  H # = 4.46 kcal mol -1 ;  S # = kcal mol -1 K -1 / +7.5 cal mol -1 K -1 (eq->#) Coefficient values ± one standard deviation a= ± b= ± Lay:,0 Gr: Average:+/- C3,C5 analysis:

Or parabola fit: T corr G#G# (eq->#) Coefficient values ± one standard deviation K0= ± 4.34 K1= ± K2= ± Lay:,0 Gr: Average:+/- C3,C5 analysis:

Lay:,1 Gr:1 TNMR [K]Tcorr [K] k(eq->ax): Simulation: Red: exp./black dots: calc. C3,C5 eq ax

k eq,ax (s -1 ) Calc.Exp. T(K)