Anodic oxidation of methylbenzenes at potentials in the first voltammetric wave

Abstract

The mechanism of the anodic oxidation of hexamethylbenzene, durene, and mesitylene in acetonitrile at the first anodic wave is discussed on the basis of data from product studies, specular reflectance spectroscopy, linear sweep voltammetry, controlled potential coulometry, and measurements at a rotating disc electrode. The oxidation waves are shown to involve the transfer of two electrons with the formation of the corresponding carbonium ions. In the case of mesitylene, the process is seen to follow an e.c.e. sequence in which the proton loss from the cation radical formed in the first electron transfer is sufficiently slow to be detectable on the time scale of the experiments.