Kinetics of oxidation of 1,4-dihydroxy-, 1-hydroxy-4-methoxy-, and 1,4-dihydroxy-2-methyl-benzene by thallium(III) in aqueous perchlorate media

Abstract

The reactions of Tl^III with 1,4-dihydroxybenzene (H₂quin), 1-hydroxy-4-methoxybenzene (Hhmb), and 1,4-dihydroxy-2-methylbenzene (H₂dhmb) have been investigated in aqueous perchlorate media at various temperatures and acidities with I= 2·0M. The reaction rates are first order in the concentration of both reactants. The dependence on acidity suggests that two paths contribute to the reaction. Rate constants for Hhmb are about one half those of H₂quin, while the methyl group of H₂dhmb increases the reaction rate. A comparison is drawn between the kinetic behaviour of a series of related oxidation reactions.