Amide-directed Rhodium(III)-catalyzed C4—H Alkenylation of Indoles with gem-Difluoromethylene Alkynes

Abstract

The direct and selective C4—H functionalization of indoles remains a significant synthetic challenge. Addressing this, we disclose a highly efficient Rh(III)-catalyzed C4—H alkenylation of indoles employing gem-difluoromethylene alkynes. This directing group-assisted protocol delivers valuable difluorinated indole derivatives in excellent yields (up to 88%), with a broad substrate scope and exceptional functional group tolerance, providing a practical and versatile route for appealing indole diversification.

Keywords

C—H activation / Indole / Rhodium catalysis / gem-Difluoromethylene alkyne

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Jilin University, The Editorial Department of Chemical Research in Chinese Universities and Springer-Verlag GmbH