Magnetic nanoparticles modified with a copper(i) complex as a novel and efficient reusable catalyst for A3 coupling leading to C–N bond formation

Abstract

Propargylamines are an important and valuable family of nitrogen-containing compounds with many applications in the fields of medical, industrial, and chemical processes. One-pot multicomponent A³ coupling reactions of aldehydes, amines, and alkynes in the presence of transition metals as catalysts is an efficient strategy for preparing propargylamines. In this study, we fabricated a novel magnetically reusable copper nanocatalyst [Fe₃O₄–BIm–Pyrim–CuI] through the immobilization of the copper(I) complex on the surface of the magnetic nanoparticles modified with benzimidazole–pyrimidine ligand and evaluated its catalytic activity in the preparation of propargylamines through one-pot multicomponent A³ coupling reactions of aldehydes, amines, and alkynes. Under this catalytic system, aryl substrates with both electron-donating and electron-withdrawing substituents also gave the desired products in excellent yields under standardized conditions. The Fe₃O₄–BIm–Pyrim–CuI catalyst was easily separated using an external magnet, and the recovered catalyst was reused in 8 cycles without significant loss of activity.