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Natural abundance 17O NMR spectroscopic study of quinone methides

✍ Scribed by David W. Boykin; Arvind Kumar; Sergey M. Shevchenko

Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
332 KB
Volume
30
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The ^17^O NMR chemical shift data for a series of substituted 10‐methyleneanthrones and related 10‐alkylanthrones in acetonitrile solution at 75°C are reported. The ^17^O NMR chemical shift value of 10‐methyleneanthrone is shielded by ca. 35 ppm compared with that of anthraquinone. The chemical shifts of the 10‐methyleneanthrones range from 493 ppm for 10‐bromomethyleneanthrone to 440 ppm for 10‐diethylaminomethyleneanthrone. A correlation of the ^17^O NMR chemical shifts of the 10‐substituted methyleneanthrones with σ^+^ constants is noted.

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