Xylylenes are molecules of considerable theoretical and synthetic interest, which have been detected and characterized by different spectroscopic methods.1 Although benzylic dichlorides have been used as very simple and readily accessible precursors, the involved mechanisms are not com- pletely understood.2 It has been recently reported3 that 266 nm laser irradiation of a,aA-dichloro-o-xylene (1a) produces the dissociation of both C–X bonds via a two- ...