Radical decomposition of various peranhydrides and peresters

Abstract

AbstractWe have studied the kinetics and the products of the thermal degradation of acetylcyclohexylsulfonyl (I), dibenzyl (II) and dicyclohexyl peroxide carbonate (III) in various solvents. The kinetic data show that the degradation is first‐order with respect to the peroxide. The activation energies for the reaction in benzene, isopropyl alcohol and carbon tetrachloride have been calculated. It is suggested that the primary process is decomposition of the peroxide to free radicals according to the scheme: magnified imageIn solvents which easily give up hydrogen, such as isopropyl alcohol, hydrogen is removed with the formation of sulfonic acids from I and the corresponding alcohols from II and III: magnified imageIn benzene and carbon tetrachloride the ensuing free radicals disproportionate, forming chiefly unsaturated sulfonic acids on degradation of I, and carbonyl compounds and alcohol on degradation of II and III. magnified imageIt should be mentioned that no products of interaction with the solvent were found on degradation of peroxydicarbonates in benzene. In the degradation of (I), a resin was isolated, of which the nature was determined by decomposition in C14‐labeled benzene. Also in the degradation of I, methyl sulfonate was detected in amounts which underwent almost no change on variation in concentration of I. This indicates that the methyl sulfonate was formed by the molecular decomposition of the initial peroxide: magnified image