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.