Photolysis of the ion pair triphenylsulfonium thiophenolate induced by outersphere charge transfer excitation

Abstract

The ion pair Ph3S+PhS- can be viewed as a sulfur-based mixed-valence system which is characterized by a PhS- to Ph3S+ outersphere charge transfer (OSCT) absorption at lambda(max) = 390 nm (in CHCl3). OSCT excitation leads to the radical pair Ph3S/PhS which undergoes subsequent elimination and radical coupling processes with the final formation of Ph2S. The photolysis proceeds with a quantum yield of phi = 0.23 at lambda(irr) = 436 nm. (C) 2003 Elsevier B.V. All rights reserved.