Palladium-Catalyzed Synthesis of Indoles by Reductive N-Heteroannulation of 2-Nitrostyrenes

1997/08/01 by Björn C. Söderberg, Björn C.G. Söderberg, James A. Shriver · 6 citations
Chemistry · #Catalytic C–H Functionalization Methods #Asymmetric Hydrogenation and Catalysis #Chemical Reaction Mechanisms

paper · doi:10.1021/jo970516+

Abstract

A palladium−phosphine catalyzed reductive N -heteroannulation of 2-nitrostyrenes, in the presence of carbon monoxide, producing indoles has been developed. Indoles were obtained, in moderate to excellent yield, from substituted 2-nitrostyrenes having either electron-withdrawing (NO 2 and CO 2 Me) or electron-donating (Br, OH, Me, OMe, and OTf) substituents on the aromatic ring. Best results were obtained using palladium diacetate (6 mol %) together with triphenylphosphine (24 mol %) as the catalytic system, under 4 atm of carbon monoxide in acetonitrile at 70 °C. Other palladium(II) and palladium(0) complexes also catalyze the reaction.

Cited by

• Practical Methodologies for the Synthesis of Indoles
• Synthesis and Functionalization of Indoles Through Palladium-catalyzed Reactions
• Recent developments in indole ring synthesis—methodology and applications
• Continuous Flow Synthesis of Heterocycles: A Recent Update on the Flow Synthesis of Indoles. [europepmc]
• Formic Acid as Carbon Monoxide Source in the Palladium-Catalyzed N-Heterocyclization of o -Nitrostyrenes to Indoles. [europepmc]
• Carbonylative synthesis and functionalization of indoles. [europepmc]

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