A Co‐Ni‐CM Heterogeneous Catalyst for the Direct Synthesis of Amides from the Oxidative Coupling of Aldehydes with N‐Substituted Formamides

Co−Ni-CM catalyst with the high catalytic performance for the oxidative amidation of aldehydes and N-substituted formamides has been synthesized. This protocol features a wide range of aldehydes and N-substituted formamides providing various amides in moderate to excellent yields with a low catalyst dosage under mild conditions.

Abstract

Given the importance of amides in pharmaceutical and chemical industries, a Co−Ni composites (Co−Ni-CM) heterogeneous catalytic system for the synthesis of amides from the oxidative coupling of aldehydes with N-substituted formamides has been developed under mild conditions. The catalyst was prepared by pyrolysis under ambient atmosphere using Co-BTC supported NiCl₂ as a precursor. The catalytic system possesses good catalytic ability and good compatibility with functional groups. The surface morphology and internal element composition of the catalyst were characterized by powder X-ray diffraction (XRD), BET adsorption, high resolution transmission electron microscope (HRTEM), scanning electron microscope (SEM), inductively coupled plasma emission spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS). The results show that the interaction of Co−Ni is a key factor for the good catalytic activity of the catalyst. Then control experiments related to the mechanism of this transformation indicate a free radical process is involved in this transformation. More importantly, the catalyst has an excellent recycling performance and can be recycled seven times without obvious loss of catalytic activity.

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