KrF excimer laser photolysis of 1,2-bis(substituted-methyl)benzenes in the presence of alkenes and acetylene; two-photon formation of o-quinodimethane and its cycloaddition with dienophiles

Abstract

o-Quinodimethane 3 is generated effectively by Krf excimer laser (248 nm) photolysis of 1,2-bis(phenoxymethyl)-, 1,2-bis(phenylthiomethyl)- and 1,2-bis(phenylselenomthyl)-benzene via a two-photon process; cycloaddition of 3 with several dienophiles gives corresponding adducts in a maximum yield of 48%.