Photoinduced thiotelluration of isocyanides by using a (PhS)2–(PhTe)2 mixed system, and its application to bisthiolation via radical cyclization

Upon visible light irradiation, highly selective thiotelluration of isocyanides bearing an electron-withdrawing group like nitro or trifluoromethyl group takes place smoothly by the use of a disulfide–ditelluride mixed system. The application of this photoinduced reaction to radical cyclization of o-vinyl and o-allyl substituted phenylisocyanides successfully leads to the formation of bisthiolated indole and quinoline derivatives, respectively, in moderate yields.