Photocyclization reactions of aryl polyenes—III : The photocyclization of 1,8-diphenyl-1,3,5,7-octatetraene and 1,10-diphenyl-1,3,5,7,9-decapentaene

Abstract

The photocylization-oxidation reaction of 1,8-diphenyl-1,3,5,7-octatetraene gave 1-phenylphenanthrene and a trace of 9-phenylphenanthrene. It was shown that 1-(α-naphthyl)-4-phenyl-1,3-butadiene and o-phenylstilbene may be intermediates in the formation of the photoproducts of 1,8-diphenyl-1,3,5,7-octatetraene. The irradiation of 1,10-diphenyl-1,3,5,7,9-decapentaene yields picene. It was demonstrated that 1-(α-naphthyl)-6-phenyl-1,3,5-hexatriene, 1,2-di-(α-naphthyl)ethylene, and 1-styrylphenanthrene are likely intermediates involved in the formation of picene.