Dynamic NMR as a Nondestructive Method for the Determination of Rates of Dissociation. XX. Secondary Isotope Effect on Kinetic Basicity of Amine Ligands in Boronate-Amine Complexes and Ammonium Salts

Article abstract of DOI:10.1246/bcsj.65.2215

Secondary isotope effects on the kinetic basicity of amine ligands in boronate-amine complexes and ammonium salts were first determined by taking advantage of the rate constants of the dissociation of the amine ligands measured by the dynamic NMR method.The basicities of amine ligands are enhanced by the α-deuterations in the both compounds and the isotope effect caused by a deuterium is larger in the boronate complexes than the ammonium salts.These isotope effects are discussed on the basis of the inductive and steric effects.