Chemical shifts of the protons within a methyl group in a saturated hydrocarbon. Slow methyl group rotation

被引:4
作者
Anderson, JE
机构
[1] Chemistry Department, University College, London, WC1E 6BT, Gower Street
关键词
D O I
10.1039/cc9960000093
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
In the proton NMR spectrum of both (Bu(t))(3)CH and (Bu(t))(3)COH at -150 degrees C, one of the three separate signals for the methyl groups of a tert-butyl group appears as three singlets of equal intensity, with a greater than 1 ppm range of chemical shifts, showing that one methyl group is rotating slowly on the NMR timescale with a barrier to 120 degrees rotation of 5.3 kcal mol(-1) (1 cal = 4.184 J).
引用
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页码:93 / 95
页数:3
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