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
A new cyclic bis-selenide containing benzylic methylene groups and a naphthalene ring, 8,13-dihydrobenzo[g]naphtho[1,8-bc] [1,5]diselenonin (1), was stable in the dark; however, the C-Se bond of 1 was readily cleaved to form o-xylylene (2) and naphtho[1,8-cd]-1,2-diselenole (3) under the scattered light in the laboratory. The o-xylylene generated from 1 under the scattered light or UV irradiation (254 nm) was trapped by several dienophiles.