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Selective population transfer in 15N and 13C NMR: Signs of 15NH and 15N13C coupling constants in secondary amide and iminium salts

✍ Scribed by H. Martineau; M. Trierweiler; M. L. Martin

Publisher: John Wiley and Sons
Year: 1981
Tongue: English
Weight: 389 KB
Volume: 17
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270170310

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✦ Synopsis

Abstract

The selective population transfer method has been applied to the study of a secondary amide and of the corresponding iminium salt. Important signal‐to‐noise enhancements were accessible in both fully coupled and proton decoupled ^15^N and ^13^C spectra. Moreover, the resolving power of the method was exploited for the accurate determination of long range ^15^N^1^H coupling constants. Experiments in which the selective inversion of transitions pertaining to the ^15^N satellite spectrum of multiplets which themselves constitute the ^13^C satellite spectrum of the main proton resonances could be carried out. The influence of a change from the amide to the iminium structure on the magnitudes and the signs of various ^15^N^1^H and ^15^N^13^C coupling constants is discussed.

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