Polyacrylonitrile Fiber Supported <i>N</i>-Heterocyclic Carbene Ag(I) As Efficient Catalysts for Three-Component Coupling and Intramolecular 1,3-Dipolar Cycloaddition Reactions under Flow Conditions

Abstract

A series of recoverable and reusable N-heterocyclic carbene silver complexes supported on polyacrylonitrile fiber were prepared and characterized. Their catalytic performances in three-component coupling reactions of aldehydes, amines, and alkynes (A3 coupling) to synthesize propargylamines were evaluated. The catalysts were also used to prepare fused triazoles in one-pot reactions with excellent yields and diastereoselectivities. In these reactions, the substrates underwent A3 coupling followed by intramolecular 1,3-dipolar cycloaddition. The above reactions were also successfully performed in a continuous-flow process, and sustainable, modular, and efficient syntheses of propargylamines and fused triazoles were achieved.