Additivity of substituent effects in the alkaline hydrolysis of alkyl benzoates

Abstract

The kinetics of hydrolysis of some methyl, ethyl, isopropyl, and t-butyl esters of substituted benzoic acids were studied in 70% v/v dioxan–water. The substituent effects and their additivity were examined. The hydrolysis of the methyl benzoates follows the sequence of relative rates (at 40°) 4-nitro 71, 2-methyl-4-nitro 11, parent 1.0, 3-methyl 0.71, 4-methyl 0.51, 2-methyl 0.14, 2,5-dimethyl 0.090, 2.3-dimethyl 0.065, 2,4-dimethyl 0.055. 2-ethyl 0.046.