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Spin—spin couplings between 13C nuclei in five-membered heteroaromatic ring systems

✍ Scribed by Michal Witanowski; Zenobia Biedrzycka

Publisher
John Wiley and Sons
Year
1994
Tongue
English
Weight
421 KB
Volume
32
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

A set of 14 ^1^J(CC) spin—spin coupling constants are reported for 11 five‐membered heteroaromatic molecules, including all relevant diazole, triazole, oxazole, oxadiazole, thiazole and thiadiazole systems. The couplings show a clear distinction between carbon—carbon bonds which are formally double or single, respectively. There seems to be no correlation of the couplings with the bond lengths concerned, in spite of some apparent trends. Potential applications of the couplings are discussed in assessing the aromaticity of five‐membered heterocycles.

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