Direct comparison of photoefficiencies of C–C bond scission in radical cations generated by photosensitized electron transfer and by irradiation of charge-transfer complexes

Abstract

Quantum yields for C–C bond scission are at least 50 times larger in radical cations of methoxybicumenes (1˙⁺) generated by quenching of the p-tetrachlorobenzoquinone (TCBQ) excited state (a process that results in triplet solvent-separated ion pairs) than in those obtained by the irradiation of [TCBQ ⋯(1)] charge-transfer complexes (a reaction that yields singlet contact ion pairs).