PIII‐Chelation‐Assisted Indole C7‐Arylation, Olefination, Methylation, and Acylation with Carboxylic Acids/Anhydrides by Rhodium Catalysis

4 in 1: P^III‐chelation‐assisted group coordinates to the rhodium(I) catalyst and directs C−H activation to the indole C7‐position, which then allows for a series of selective C−H functionalization with carboxylic acids or anhydrides.

Abstract

Rhodium‐catalyzed C7‐selective decarbonylative arylation, olefination, and methylation of indoles with carboxylic acids or anhydrides by C−H and C−C bond activation have been developed. Furthermore, C7‐acylation products can also be generated selectively at a lower reaction temperature in the developed system. The key to the high reactivity and regioselectivity of this transformation is the appropriate choice of an indole N‐PtBu₂ chelation‐assisted group. This method has many advantages, including easy access and removal of the directing group, the use of cheap and widely available coupling agents, no requirement of an external ligand or oxidant, a broad substrate scope, high efficiency, and the formation of a sole regioisomer.

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