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NMR studies in the heterocyclic series. XVIII—Carbon-13 NMR study of azolium salts. Attempted correlation of chemical shifts with calculated charge densities

✍ Scribed by Jean-Pierre Fayet; Marie-Claire Vertut; Alain Fruchier; El Mostafa Tjiou; José Elguero

Publisher: John Wiley and Sons
Year: 1978
Tongue: English
Weight: 385 KB
Volume: 11
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270110503

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✦ Synopsis

Abstract

The carbon‐13 chemical shifts and the ^1^J(CH) coupling constants for 18 azolium salts (di‐N‐methyl‐pyrazolium, ‐indazolium, ‐benzimidazolium and ‐benzotriazolium iodides) have been determined and assigned. The chemical shifts are discussed as a function of substituent effects, positive charge introduction and total electronic density (calculated by the CNDO/2 method). The general problem of correlations between chemical shifts and total charge densities in azoles is discussed. A statistical approach shows that these correlations are of poor quality.

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