Cu-catalyzed borylative cyclization of N-(o-alkynylaryl)imines

Abstract

We report herein the first copper-catalyzed intramolecular borylative cyclization of alkynes with imines, providing efficient access to alkenyl boronate-containing indolines. Preliminary mechanistic studies suggested a nucleophilic addition process for the alkenyl copper-trapping step, in which the nucleophilicity of alkenyl copper was largely enhanced by the formation of boronate complexes.