SYNTHESIS OF SOME PYRROLO[4,3,2-DE]QUINOLINES

The selenium dioxide oxidation of the methyl group in 5-acetamido-6-methoxy-4-methylquinoline produced 1,2-dihydro-8-methoxy-2-oxopyrrolo[4,3,2-de]quinoline, 8b. Halogenation and nitration of 8b gave and 6-substituted derivatives 8c-e. 6-Halo-1,2-dihydro-8-methoxy-2-oxopyrrolo[4,3,2-de]quinolines were O-demethylated, giving phenols 8g and 8h. Reaction of 8b, and its N-methyl derivative 8i, with iodomethane resulted in quaternization of the quinoline ring nitrogen; borohydride reduction of the salts thus produced, and then aerial oxidation, led to dioxindoles 12a,b and 13a,b. Lithium aluminum hydride reduction of 12a produced indole 10b.