Nuclear magnetic resonance spectroscopy. Barriers to internal rotation in some halogenated methylbutanes
作者:John D. Roberts、Bruce L. Hawkins、Wolfgang Bremser、S. Borcic
DOI:10.1021/ja00747a022
日期:1971.9
Barriers to internal rotation about the C(2)-C(3) bonds have been determined for ten closely related halogenated methylbutanes by detailed line-shape analysis of their nuclear magnetic resonance spectra. The experimental barriers range from 9 to 16 kcal/mol. In addition, for some of the compounds investigated, free energy differences were obtained for rotational isomers under conditions of slow conformational
十种密切相关的卤代甲基丁烷通过对其核磁共振谱的详细线形分析确定了 C(2)-C(3) 键内部旋转的障碍。实验屏障范围为 9 至 16 kcal/mol。此外,对于一些研究的化合物,在缓慢的构象交换条件下获得了旋转异构体的自由能差异。结果根据可能的非键相互作用进行讨论。