HOMOLYTIC DECOMPOSITIONS OF HYDROPEROXIDES .2. RADICAL-INDUCED DECOMPOSITIONS OF T-BUTYL HYDROPEROXIDE

Three factors account for deviations from the simplest pattern for the radical-induced decomposition of t-BuO2H (reactions 1-4 in part I): (1) variation in the ratio of terminating to nonterminating interactions of 2t-BuO2· with the viscosity of the medium; (2) competition between the propagation and cleavage reactions of t-BuO· radicals; and (3) competition between hydroperoxide and solvent for t-BuO· radicals. Reactions in the gas phase illustrate all three factors. In solution cleavage is important at high temperatures and low concentrations of t-butyl hydroperoxide (as in 0.1 M t-BuO2H in benzene or CCl4 at 100°) or in hydroxylic solvents (AcOH or t-BuOH) at moderate temperatures. Attack on alkane solvents increases with increasing temperature. Chain lengths of 1 to 50 are observed. Both cleavage and solvent participation result in shorter chains and complex kinetics. © 1968, American Chemical Society. All rights reserved.