The methanolysis of nitrophenyl esters. Part III. The kinetics of the base-catalysed methanolysis and pyridinolysis of 2,4-dinitrophenyl toluene-p-sulphonate

Abstract

The methanolysis of 2,4-dinitrophenyl toluene-p-sulphonate has been studied in the presence of tertiary bases. Depending on the steric properties and the basic strength of the nucleophile, either sulphur–oxygen fission or aryl–oxygen and sulphur–oxygen fission were observed, and were shown to proceed by the bimolecular mechanism. Steric requirements of the nucleophile in the case of aryl–oxygen fission were critical. Catalytic constants for sulphur–oxygen fission, in the presence of equally sterically hindered bases, followed the Brönsted law.