107469-24-9Relevant articles and documents
Condensed Heteroaromatic Ring Systems. VI. Synthesis of Indoles and Pyrrolopyridines from o-Nitroarylacetylenes
Sakamoto, Takao,Kondo, Yoshinori,Yamanaka, Hiroshi
, p. 2362 - 2368 (2007/10/02)
Catalytic hydrogenation of o-nitrophenylacetaldehyde diethyl acetal over palladium-carbon, followed by intramolecular cyclization of the resulting o-aminophenylacetaldehyde diethyl acetal with hydrochloric acid, gave indole.Similarly, 4-methylindole, ethyl 5-indolecarboxylate, and various pyrrolopyridines were synthesized from the corresponding o-nitroarylacetaldehyde derivatives.The preparation of the desired o-nitroarylacetaldehydes was accomplished by the condensation of o-halonitroaromatics with trimethylsilylacetylene in the presence of dichloro-bis(triphenylphosphine)palladium as a catalyst, followed by ethanolysis of the resulting o-(trimethylsilylethenyl)nitroaromatics.Keywords - o-halonitroaromatic; o-cyanohaloaromatic; trimethylsilylacetylene; palladium-catalyzed reaction; cyclization; indole; pyrrolopyridine