Preparation and characterization of copper/polysulfonamide complex immobilized on geraphene oxide as a novel catalyst for the synthesis of pyrimido[1,2‐a]benzimidazoles
Nayereh Shekarlab, Ramin Ghorbani‐Vaghei, Sedigheh Alavinia
Abstract
Copper–polysulfonamide complex immobilized on geraphene oxide as a novel heterogeneous catalyst (GO@PSA‐Cu) was synthesized and the structure and morphology of catalyst were characterized with various analytical techniques such as Fourier‐transform infrared spectroscopy, scanning electron microscopy, energy‐dispersive X‐ray, N 2 isotherms, elemental mapping, inductively coupled plasma–MS, and thermogravimetric analysis. The GO@PSA‐Cu catalyst demonstrated good to excellent yields for the synthesis new derivatives of pyrimido[1,2‐a]benzimidazoles via one‐pot three‐component condensation reaction of various aromatic aldehydes, 2‐aminobenzimidazole, and ethyl acetoacetate in ethanol. The method presented herein has several prominent advantages such as cost‐effectiveness, operational simplicity, short reaction times, high yields, and reusability of the catalyst even after six consecutive runs.