Intramolecular Ritter reactions of 2-(2-cyanoethyl)tetrahydrocyclopenta[b]indole and -carbazole derivatives

Intramolecular Ritter reactions of 2-(2-cyanoethyl)tetrahydrocyclopenta[b]indole and -carbazole derivatives, prepared by a sequence of two different alpha-substitutions and Grignard reactions of the indole-based ketones 4-methyl-1,4-dihydrocyclopenta[b]indol-3(2H)-one and 9-methyl-2,3,4,9-tetrahydro-1H-carbazol-1-one, were used as key steps in the construction of various tetracyclic lactam compounds.