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Some aspects of anisochronism of geminal methyl groups in quaternised α-dimethylamino esters (1H and 13C NMR)

✍ Scribed by Janusz Da̧browski; Andrzej Ejchart; Krystyna Kamieńska-Trela

Publisher
John Wiley and Sons
Year
1973
Tongue
English
Weight
376 KB
Volume
5
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The magnitude of chemical shift nonequivalence (Δδ) in compounds having the general formula R^1^CH(COOR^2^)N^+^R^3^Me~2~X^−^ is discussed from the viewpoint of selective shielding of one of the geminal groups by the ester group in the preferred rotamer. In addition, a novel example of the increase of Δδ with rise in temperature has been observed.

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