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Deuterium isotope effect on 13C chemical shifts of tetrabutylammonium salts of Schiff bases amino acids

✍ Scribed by Z. Rozwadowski

Publisher
John Wiley and Sons
Year
2006
Tongue
English
Weight
155 KB
Volume
44
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Deuterium isotope effects on ^13^C chemical shift of tetrabutylammonium salts of Schiff bases, derivatives of amino acids (glycine, L‐alanine, L‐phenylalanine, L‐valine, L‐leucine, L‐isoleucine and L‐methionine) and various ortho‐hydroxyaldehydes in CDCl~3~ have been measured. The results have shown that the tetrabutylammonium salts of the Schiff bases amino acids, being derivatives of 2‐hydroxynaphthaldehyde and 3,5‐dibromosalicylaldehyde, exist in the NH‐form, while in the derivatives of salicylaldehyde and 5‐bromosalicylaldehyde a proton transfer takes place. The interactions between COO^−^ and NH groups stabilize the proton‐transferred form through a bifurcated intramolecular hydrogen bond. Copyright © 2006 John Wiley & Sons, Ltd.

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