Kinetic studies of the hydrolysis of α-amino acid esters

Abstract

The rate of acid-catalysed hydrolysis of ethyl glycinate has been shown to be considerably slower than that of ethyl acetate, contrary to previously published results. The rates of alkaline hydrolysis of some ethyl esters of common amino acids have been obtained, and are in agreement with results in the literature. Some aromatic aldehydes, carbon dioxide, and imidazole have been shown to be efficient catalysts for the hydrolysis of the p-nitrophenyl esters of glycine, leucine, and phenylalanine. Both the aromatic aldehydes and carbon dioxide appear to catalyse the reactions by forming addition compounds with the unprotonated amino group of the ester. In the case of aldehyde catalysis, results suggest that the rate determining step is the decomposition of the carbinolamine intermediate, whereas for catalysis by carbon dioxide, formation of the carbamate intermediate seems to be rate determining.