Mononuclear heterocyclic rearrangements. Part 15. Kinetic study of the amine-catalysed rearrangement of some Z-arylhydrazones of 3-benzoyl-5-phenylisoxazole into 2-aryl-4-phenacyl-5-phenyl-1,2,3-triazoles in acetonitrile and in benzene

Abstract

The kinetics of the title reaction have been measured in the presence of n-butylamine, piperidine, triethylamine, and diazabicyclo[2.2.2]octane (DABCO). The reaction has also been studied in the presence of pairs of amines [butylamine (or piperidine) and triethylamine (or DABCO)] in benzene. The results confirmed the lower reactivity of isoxazole derivatives with respect to 1,2,4-oxadiazole derivatives (rate ratios ca. 10^–3). The kinetic laws observed are accounted for by the ‘catalysis of catalysis’ mechanism.