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A GIAO/DFT study of 1H, 13C and 15N shieldings in amines and its relevance in conformational analysis

✍ Scribed by Ibon Alkorta; José Elguero

Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
163 KB
Volume
42
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The ^1^H, ^13^C and ^15^N absolute shieldings of 13 amines were calculated at the GIAO/B3LYP/6–311++G** level. For some compounds (ethylamine, piperidine and 1‐methylpiperidine) two conformations were calculated. The ^13^C and ^15^N data could be correctly correlated with experimental chemical shifts, allowing the conformation of 1‐methylpiperidine to be established. The ^1^H NMR absolute shieldings, although less well correlated with δ values, were used to account for the anisotropy effects of the N lone pair. Copyright © 2004 John Wiley & Sons, Ltd.

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