Synthesis of Indole-Fused Oxepines via C–H Activation Initiated Diastereoselective [5 + 2] Annulation of Indoles with 1,6-Enynes

作者：Xiaoli Huang, Yan Shi, Yongzhuang Wang, Jiao Jiao, Yuhai Tang, Jing Li, Silong Xu, Yang Li · 发表于：Organic Letters · 年份：2021 · DOI：10.1021/acs.orglett.1c03106 · 被引用次数：27 · 研究领域：Catalytic C–H Functionalization Methods、Synthesis and Catalytic Reactions、Cyclopropane Reaction Mechanisms

A rhodium-catalyzed diastereoselective formal [5 + 2] annulation of indoles with cyclohexadienone-containing 1,6-enynes has been established via indole 2,3-difunctionalization. The reaction, probably proceeding through tandem indole C2–H alkenylation and intramolecular Friedel–Crafts alkylation relay, provides rapid construction of indole-fused oxepines in good to excellent yields with a broad substrate scope. This method also features concomitant construction of cis -hydrobenzo[ b ] oxepine scaffolds, a core unit found in numerous natural products of important biological activities.