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Deuterium isotope effects on 13C nuclear shielding as a measure of tautomeric equilibria

✍ Scribed by Poul Erik Hansen; Fritz Duus; Peter Schmitt

Publisher: John Wiley and Sons
Year: 1982
Tongue: English
Weight: 268 KB
Volume: 18
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270180114

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✦ Synopsis

Abstract

Large deuterium isotope effects of both signs have been observed on the ^13^C nuclear shielding in proton‐chelating tautomeric forms of β‐thioxoketones, and small isotope effects of both signs have been found in related forms of Schiff's bases of salicylaldehydes. These effects are interpreted in terms of shifts in the tautomeric equilibria on deuterium substitution of the enolic proton. The observation of deuterium isotope effects is suggested as a useful method for the detection of fast tautomeric equilibria in systems of the following type.
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