Catalytic activity of Cu nanoparticles supported on Fe3O4–polyethylene glycol nanocomposites for the synthesis of substituted imidazoles

Abstract

In the present study, we carried out chemical synthesis and characterization for a Fe₃O₄–polyethylene glycol–Cu nanocomposite (Fe₃O₄–PEG–Cu). Firstly, poly(ethylene glycol) was functionalized using cyanuric chloride (PEG-Cl₄). Then PEG-Cl₄ was linked with Fe₃O₄ nanoparticles via formation of covalent bonds (Fe₃O₄–PEG). The Cu nanoparticles were supported by reducing copper ammonia complexes with hydrazine hydrate on the surface of this nanocomposite. Nanoparticles have been characterized by FT-IR, XRD, SEM, EDAX, TGA-DTA, AAS and VSM techniques. The catalytic activity of the Fe₃O₄–PEG–Cu catalyst was evaluated for the synthesis of highly substituted imidazoles. This new catalyst was found to be a highly active and green catalyst for the synthesis of 2,4,5-trisubstituted imidazoles and 1,2,4,5-substituted imidazoles. The synthesized catalysts displayed magnetic properties, which allowed their fast separation from the reaction medium using a simple magnet.