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High resolution NMR spectroscopy of heteroaromatic cations. I. 13C1H coupling constants in the pyridinium cation

✍ Scribed by P. Sándor; L. Radics

Publisher
John Wiley and Sons
Year
1980
Tongue
English
Weight
467 KB
Volume
14
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

High‐resolution ^1^H{^14^N} and proton‐coupled natural‐abundance ^13^C{^14^N} double resonance spectra have been recorded for pyridinium tetrafluoroborate dissolved in CD~3~CN. Iterative analysis of these spectra has provided the accurate values and relative signs of all possible long‐range ^13^C—^1^H coupling constants. These are compared with the respective values in pyridine and pyridine‐N‐oxide and discussed in terms of the relationship with the electronegativity of the N‐substituent. Experimental conditions allowing the observation of well‐resolved proton‐coupled ^13^C NMR spectra of charged heteroaromatics are also presented.

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