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Differentiation between isomeric structures of benzazoles by 14N, 13C and 1H NMR

✍ Scribed by Lech Stefaniak

Publisher
John Wiley and Sons
Year
1978
Tongue
English
Weight
254 KB
Volume
11
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Nitrogen chemical shifts constitute an effective means of distinguishing between isomeric benzazole ring systems. There is a large difference in nitrogen shielding, usually more than 20 ppm, between isomeric benzenoid‐ and quinonoid‐like structures. ^13^C and ^1^H NMR is shown to provide unambiguous structure assignment only in cases of symmetric quinonoid ring systems of azoles.

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