Geminate reverse electron transfer in a photogenerated ion-pair. Mechanism of 1,4-dicyanonaphthalene sensitized ylide formation from stilbene oxides

Abstract

The 337.1 nm laser photolysis of 1,4-dicyanonaphthalene (sensitizer) in the presence of cis and trans stilbene oxides as quenchers (donors) shows the ready formation of mixtures of kinetically distinct isomeric carbonyl ylides on the time scale of sensitizer fluorescence quenching; geminate reverse electron transfer in photogenerated ion-pairs containing ring-opened radical-cations of oxiranes is responsible for the fast production of ylides.