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 internalrotation 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