Nucleophilic catalysis. Part III. Acid-catalysed hydrolyses of 3-phenylsydnone and 3-m-nitrophenylsydnone

Abstract

The effects of added acids and salts on the hydrolyses of 3-phenylsydnone and 3-m-nitrophenylsydnone have been studied in both water and aqueous dioxan as solvents. The mechanism of hydrolysis is shown to involve specific hydrogen ion catalysis and nucleophilic catalysis by the anions of the acids involved. Values of the Hammett acidity function H₀ are reported for hydrochloric and hydrobromic acids in 40% dioxan–water.