Kinetics and mechanism of base hydrolysis of a-aminoacid esters catalysed by [pd(1,3-diamino-2-hydroxypropane)(H2O)2]2+ complex

Abstract

Amino acid esters (L) react with [Pd(DHP(H2O)2] 2+ , (DHP = 1,3-diamino-2-hydroxopropane) giving mixed ligand [Pd(DHP)L]2+ The kinetics of hydrolysis of [Pd(DHP)L]2+ have been studied by pH-stat technique and rate constants were obtained. Rate acceleration observed for glycine methyl ester is high. The effect with methionine methyl ester and histidine methyl ester are much less marked, as the mixed-ligand complexes with these ligands do not involve alkoxycarbonyl donors. Possible mechanisms for these reactions are considered. Activation parameters have been determined for glycine methyl ester.