Chiral Phosphoric Acid‐Catalyzed Chemo‐ and Enantioselective N‐Alkylation of Indoles with Imines

A chemo- and enantioselective protocol for the N-alkylation of indoles with imines was developed. This process was catalyzed by a BINOL-derived phosphoric acid catalyst to give the corresponding acyclic aminals of indoles in 46-99% yields with 70-98% ee. The application of this method for the "late-stage" functionalization of a bioactive compound was performed with high efficency. The products showed good stability and enabled many further transformations.