Cu‐supported amine‐functionalized Fe3O4 magnetically recoverable nanocatalyst for A3 coupling reactions

Abstract

In this study, a Cu‐supported amine‐functionalized Fe3O4 nanocatalyst (Fe3O4‐NH2‐Cu) has been synthesized for A3 (amine, aldehyde, and alkyne) coupling reactions. The synthesized nanocatalyst was characterized by PXRD, FT‐IR, FESEM‐EDX, XPS, and VSM analysis. The catalytic action of the synthesized Fe3O4‐NH2‐Cu nanocatalyst was evaluated for A3 coupling reactions, with an excellent product yield of 97% in propargylamine synthesis and 98% in indolizines synthesis, respectively. The substrate scope of the catalyst was validated for various amines, substituted aryl aldehydes, and phenyl acetylene. The uniqueness of the synthesized nanocatalyst is effective performance of the catalyst under solvent‐free conditions and less reaction time for the aforementioned application. With the aid of an external magnet, the catalyst can be easily recovered from the reaction mixture and reused at least for five times without significant loss in catalytic activity, and its structural stability was confirmed by XRD, FT‐IR, and FESEM‐EDX analysis of the recovered catalyst. Overall, it is a green approach to synthesize simple Fe3O4‐NH2‐Cu catalytic system with magnetic recoverability, reusability, and recyclability for A3 coupling reactions under solvent‐free conditions with broad substrate scope. The proposed plausible mechanism is supported by DFT studies.