β-Deuterium Isotope Effects on Amine Basicity, “Inductive” and Stereochemical
作者:Charles L. Perrin、Brian K. Ohta、Joshua Kuperman
DOI:10.1021/ja038343v
日期:2003.12.1
Secondary beta deuterium isotope effects on acidity constants of ammonium ions are measured using a remarkably precise NMR titration method. Deuteration is found to increase the basicity of methylamine, dimethylamine, benzylamine, and N,N-dimethylaniline. The effect is attributed to a lowered zero-point energy of a CH bond adjacent to an amine nitrogen. The method permits a determination of the stereochemical