Photocyclization Reactions of Aryl Polyenes. IV. The Syntheses of Isatogens and Isatogen-like Compounds

Abstract

Photochemical reactions of 1-o-nitrophenyl-4-phenyl-1,3-butadiene, 1,4-di-o-nitrophenyl-1,3-butadiene, 1-o-nitrophenyl-6-phenyl-1,3,5-hexatriene, and 1,6-di-o-nitrophenyl-1,3,5-hexatriene all gave the appropriate 2-substituted isatogen. The related m- and p-nitrophenyl polyenes were inert to the irradiation conditions. A six-membered ring isatogen-like compound, 2-phenyl-3-oxo-benzo[d,e]quinoline-N-oxide was prepared by irradiation of 1-[1′-(8′-nitronaphthyl)]-2-phenylacetylene. A seven-membered ring isatogen-like compound, 6-phenyl-7-oxo-dibenzo[b,d]azepine-N-oxide, was prepared by heating 1-[2-(2′-nitrobiphenyl)]-2-phenylacetylene.