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Carbon-13, proton spin–spin coupling constants in some 2-substituted propanes

✍ Scribed by Roderick E. Wasylishen; Kalvin Chum; John Bukata

Publisher
John Wiley and Sons
Year
1977
Tongue
English
Weight
366 KB
Volume
9
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Carbon‐13, proton coupling constants have been measured in eighteen different 2‐substituted propanes. ^1^J(C‐2,H) shows variations similar to those observed previously for monosubstituted methanes. ^2^J(C‐2,H) is essentially independent of the substituent at C‐2, while ^2^J(C‐1,H) varies over a range of at least 5 Hz. The latter coupling constant becomes more positive as the electronegativity of the substituent increases while ^3^J(CH) decreases as the electronegativity of the substituent increases. The observed trends in ^n^J(CH) are compared with those calculated using semi‐empirical molecular orbital theory at the INDO level of approximation.

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