Photoinduced single electron transfer reactions of bibenzyl and some of its derivatives

The photochemical reaction of bibenzyl 1, its 4,4′-dimethoxy derivative 2 and bicumyl 3 with some aromatic nitriles (leading to alkylation of the nitrile) and tetranitromethane (TNM)(leading to ring trinitromethylation or nitration) involve SET fragmentation of the radical cation (either C–H or C–C bond) and, in the case of TNM, also of the radical anion.