Photosensitized electron-transfer reactions of phenylacetylene

Abstract

Phenylacetylene (A) reacts with excited sensitizers (S) to produce radical ions (S)·^–, (A)·⁺, which react as geminate or separated pairs with (A) to give a dimeric radical cation (A⁺–·A); the latter reacts with nitriles to give pyridines (1) or with nitromethane leading to an oxidation product (2) and a dimer (1-phenylnaphthalene) is also formed via the geminate pair.