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Diamagnetic contribution and substituent effects on 13C n.m.r. spectra

✍ Scribed by Y. A. Shahab

Publisher
John Wiley and Sons
Year
1977
Tongue
English
Weight
304 KB
Volume
9
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Correction of measured chemical shifts by subtracting the diamagnetic contributions caused by certain substituents on various carbons of a molecule leads to data that allow a reasonable interpretation of substituent effects on chemical shifts in ^13^C n.m.r. spectroscopy. It is shown that both paramagnetic and diamagnetic terms increase on all carbons of a molecule when the atomic number of a substituent increases down the same group of the periodic table. An explanation of α‐, β‐, and γ‐ effects for methyl substitution using the same procedure is attempted.

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