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Spatial substituent effects of various fluorinated groups on the 13C chemical shifts in cyclohexanes

✍ Scribed by Yvan Carcenac; Patrick Diter; Claude Wakselman; Marc Tordeux

Publisher
John Wiley and Sons
Year
2007
Tongue
English
Weight
117 KB
Volume
45
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The effect of introduction of fluorinated groups (CH~2~F, CHF~2~, CF~3~, C~2~F~5~, OCF~3~, SCF~3~) on the ^13^C NMR chemical shifts in cyclohexanes is examined. The two main effects are caused by location at the α and γ carbon positions. Comparison of the various data allowed the calculation of increments corresponding to the introduction of fluorinated groups at axial or equatorial positions on the cyclohexane ring. The introduction of fluorine atoms in methoxy and thiomethoxy groups has only a slight effect through the heteroatom on the ^13^C chemical shifts. Copyright © 2007 John Wiley & Sons, Ltd.

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