STUDIES ON ENAMIDES PART-2 : A NOVEL PHOTOCHEMICAL SYNTHESIS OF 9H-INDOLOPHENANTHRIDIN-9-ONE, A BENZCANTHINE ANALOGUE

Article abstract of DOI:10.1016/S0040-4020(01)89239-5

The synthesis of 3-aroylcarbazoles <4(a-d)> and the unknown 1-aroylcarbazoles <5(a-c)> has been achieved by the photolysis of 9-aroylcarbazoles <3(a-d)> in polar solvent.Irradiation of 3(a-c) in non-polar solvent afforded regiospecifically 5(a-c), carbazole (1) and for the first time, 9H-indolo<3,2,1-de>phenanthridin-9-one (8) from 3b.The yield of 8 was significantly improved by UV exposure of 9-(2-iodobenzoyl)-carbazole (3e) in methanol and iodine, without providing any photomigrated product.