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Stereochemical aspects of proton chemical shifts. VII. The γ effects of hydroxyl, methoxyl and methyl substituents

✍ Scribed by Dirk Tavernier; Marc J. O. Anteunis

Publisher: John Wiley and Sons
Year: 1978
Tongue: English
Weight: 362 KB
Volume: 11
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270111209

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✦ Synopsis

Abstract

The ^1^H NMR chemical shifts of some hydroxy, methoxy or methyl substituted trans‐decalins, trans‐1, 3‐dioxadecalins and cyclohexanes are reported. It is concluded that the replacement in a g^+^g^+^ HCCCH fragment of one hydrogen by hydroxy, methoxy or methyl results in a modest (0.1 ppm) upfield shift of the other hydrogen atom. Experimental limitations to the transferability of shift increments from one molecular environment to another are demonstrated. The syntheses of 1α,5β‐dimethoxy‐ and 1β,5α‐dimethoxy‐trans‐decalin are given.

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