The n.m.r. spectra of 11 tetra-substituted ethanes have been obtained in a number of solvents. Changes in the vicinal coupling constants of 1-phenyl-1,2,2-trihaloethanes with solvent do not fit the electrostatic model for solvent effects. It is concluded that the theory breaks down because solute–solvent hydrogen bonding specifically favors the trans rotamers of these compounds. The conditions under
已在多种溶剂中获得了 11 种四取代
乙烷的核磁共振谱。1-苯基-1,2,2-三卤
乙烷与溶剂的邻位耦合常数的变化不符合溶剂效应的静电模型。得出的结论是,该理论崩溃了,因为溶质 - 溶剂氢键特别有利于这些化合物的反式旋转异构体。还用更一般的术语讨论了预期理论崩溃的条件。