The Base-Promoted Intermolecular Hydroamination Reaction between Olefins and Indoles

Indole, a common nitrogen-containing heterocycle found in numerous FDA-approved drugs, is widely present in diverse bioactive molecules. Conventional methods for <i>N</i>-alkylation of indoles generally require transition-metal catalysts, limiting the substrate scope and operational simplicity. The current research proposed a transition-metal-free, intermolecular hydroamination between indoles and 2-pyridinemethanol-protected 3-butenoic acid derivatives. The reaction proceeds under mild basic conditions with broad substrate compatibility, thus providing a novel and practical approach to the synthesis of <i>N</i>-alkylated indoles.