Reactions of halogenomethanes in the vapour phase. Part 2. Reactions of chloroform with indoles and pyrrolo[2,3-b]pyridines at 550 °C

Abstract

Vapour-phase reactions of chloroform with indole at 550 °C give mainly 3-chloroquinoline together with smaller proportions of 2-chloroquinoline and quinoline. C-Methylindoles similarly give the corresponding methyichloroquinolines and methylquinolines. The 2,3-cyclopentindole (20) gives mainly 3-chlorocarbazole and significant quantities of carbazole and 4-chlorocarbazole. In contrast, 1-methyl- and 1-benzyl-indole (7) afford mainly quinoline with some 3-chloroquinoline and in the case of (7) only, 2-phenylquinoline. Pyrrolo[2,3-b]pyridines (24) and (25) give mainly the corresponding 3-chloro-1,8-naphthyridines (26) and (27), though in low yield.