Copper-Catalyzed Multicomponent Coupling Reaction of Primary Aromatic Amines, Rongalite, and Alkynes: Access to -Aryl Propargylamines.

In this work, a practical copper-catalyzed multicomponent coupling reaction of primary aromatic amines, rongalite, and alkynes for the direct synthesis of -aryl propargylamines has been developed. This method could overcome the substrate limitation in A coupling reactions of primary aromatic amines, formaldehyde, and alkynes. Mechanistic studies revealed that rongalite acts as not only the active C1 unit but also the accelerator to activate the -generated -arylmethanimines for the coupling reaction with alkynes. This coupling reaction is highly efficient and features a broad substrate scope, as well as utility with scale-up synthesis and converting the corresponding product -aryl propargylamines into useful heterocyclic skeletons.