Cp*Co(III)-Catalyzed Regioselective Redox-Neutral Synthesis of 3-Alkenylated Isoquinolones from N-Chlorobenzamides with 1,3-Diynes at Room Temperature

Abstract

We have developed Cp*Co(III)-catalyzed redox-neutral synthesis of 3-alkynylated isoquinolones via (4 + 2) annulation of N-chlorobenzamides and 1,3-diynes. The reaction displayed a broad scope and functional group tolerance and performed under mild conditions at room temperature. The high regioselectivity was observed in case of meta-substituted N-chlorobenzamides as compared to our previously developed Ru-catalytic system. The reaction is operationally simple and also applicable to the broad range of substrates with good functional group tolerance.

Keywords

Alkynes - Annulation - Fused-ring systems - Metallacycles - Regioselectivity

Publication History

Received: 20 November 2025

Accepted after revision: 19 January 2026

Article published online:
03 February 2026

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