The photochemistry of distyrylbenzenes has been reinvestigated. It appears that formation of 1, 12-benzperylene from the para isomer and picene from the ortho compound occur via an indirect route; the relevant cyclizations take place only in dimers of the parent compounds. Other photoproducts from ortho distyrylbenzene are stilbene and phenanthrene, probably arising via 2, 3-diphenyl-2, 3-dihydronaphthalene. These results show that the ...
