CuCl/Et₃N‑Catalyzed Synthesis of Indanone-Fused 2‑Methylene Pyrrolidines from Enynals and Propargylamines

An efficient CuCl/Et₃N-catalyzed tandem reaction for the synthesis of indanone-fused pyrrolidine was developed. In this process, two rings and four bonds are generated in one pot with high atom-economy and step-efficiency. The addition of Et₃N was found as the key factor for the success of the tandem reaction.