Mesoionic compounds. Part 8. Acid-catalysed hydrolysis of aryloxatriazoles

Abstract

The acid-catalysed hydrolyses of some 3-(para-substituted phenyl)oxatriazoles have been studied in aqueous solutions of mineral acids at 120 °C. Analyses of the data by Bunnett, Bunnett–Olsen, and excess acidity criteria are consistent with a gradual changeover from an A-2 mechanism at low acid concentration to a predominantly A-1 mechanism at high acidities. Values of pK_BH+ of these compounds in sulphuric acid have been determined.