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Additive NMR shielding parameters for some substituted cyclohexanols

✍ Scribed by G. Ceccarelli; B. Macchia; F. Macchia; L. Monti

Book ID
102951838
Publisher
John Wiley and Sons
Year
1975
Tongue
English
Weight
596 KB
Volume
7
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The shielding effects of some substituents on the chemical shifts of the methine proton of axial and equatorial cyclohexanols have been calculated and rationalised. The remarkable downfield shift observed for the phenyl substituent has been discussed on the basis of Johnson‐Bovey and Haigh‐Mallion theories. The chemical shift of methine protons of some cyclohexanols have been calculated using additive shielding increments. Agreement between calculated and experimental values substantiates the use of the additivity principle in cyclohexyl systems and justifies the origin of certain marked inversions of the accepted rule that the axial protons resonate at lower fields than the corresponding equatorial ones.

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