Mechanisms of Singlet and Triplet Sensitized Decomposition of Bis(2-phenylbenzoyl) Peroxide

Abstract
Bis(2-phenylbenzoyl) peroxide (2-PhBPO) was found to decompose on singlet and triplet sensitized irradiations in benzene and carbon tetrachloride. The quantum yields were determined to be 0.48 and 0.43 on direct excitation and chrysene sensitization in benzene, respectively, and 0.62 and 0.60 on benzophenone and 3′-methoxyacetophenone sensitizations in carbon tetrachloride, respectively. The reaction mechanisms are discussed from the standpoint of the modes of bond cleavage.