Two-photon cleavage of benzil in the laser-jet: Intermolecular reactions of transient benzoyl and tert-butoxy radicals in the photolysis of tert-butyl peroxide mixtures

Article abstract of DOI:10.1021/ja00062a008

Normal irradiation of benzaldehyde in tert-butyl peroxide as solvent afforded benzil and minor amounts of tert-butyl benzoate (1), whereas in the laser-jet mode exclusively ester 1 was observed. On photolysis of benzaldehyde in a 1:1 mixture of tert-butyl peroxide and CCI₄ as solvent, only benzoyl chloride was found on normal irradiation. However, in the laser-jet mode also ester 1, chlorobenzene, and hexachloroethane were observed. Chlorobenzene arises from decarbonylation of the intermediary benzoyl radicals and subsequent chlorine abstraction from CCI₄ by the resulting phenyl radicals. Benzil was cleaved in the laser-jet through a two-photon process and afforded the same benzoyl radical-derived products as in the photolysis of benzaldehyde, except that also α,α,α-trichloroacetophenone (2) was formed by an in-cage reaction.