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Comparison of substituent-induced proton NMR shift in steroids and decalins

✍ Scribed by Hans-Jörg Schneider; Marion Jung

Publisher
John Wiley and Sons
Year
1988
Tongue
English
Weight
317 KB
Volume
26
Category
Article
ISSN
0749-1581

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✦ Synopsis

The proton shifts of trans-decalin and of its Phydroxy derivative were determined by 2D NMR methods, supported in the latter case by lanthanide-induced shifts. Based on these shifts and on literature data, substituent (X)-induced chemical shifts (SCS) were obtained for the PX-trans-decalins for X = OH, C1, Br, I and CH, . Comparisons with corresponding secondary cyclohexyl derivatives, derived from androstane measurements, usually showed good correlations; 38 SCS values out of 40 (for X = Hal, OH) deviate by < fO.08 ppm and are in line with earlier linear electric field effect calculations. Only two literature values for Br and I on the antiperiplanar tertiary H-10 exhibit unusual upfield shifts which, however, cannot be related to dihedral angle changes.

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