Synthesis of 2,4,6-Triaryl Pyridines Using Hydrotalcite Magnetic Nanoparticles Decorated with Cobalt

Abstract

In this study, we report a successful strategy for the immobilization of cobalt nanoparticles on the surface of the magnetic hydrotalcite Fe3O4/HT-CO. The synthesized nanocatalyst was used in a one-pot three-component synthesis of 2,4,6-triaryl pyridines using acetophenones, aryl aldehydes, and ammonium acetate under aerobic oxidation. The structural and chemical properties of the prepared nanocatalyst were affirmed by different instrumental analyses, including XRD, FE-SEM, EDX, ICPOES, TGA, FT-IR, and VSM. The aforementioned nanocatalyst could be conveniently removed from the reaction mixture upon applying an external magnetic field. The catalytic activity of the heterogeneous nanocatalyst could be maintained efficiently after recycling up to five successive runs without any noticeable decrease in its catalytic performance or any remarkable changes in catalyst structure. Solvent-free produce, simplicity of the reaction conditions, short reaction times, easy workup, reusability of catalyst, high yields of the products, as well as the use of a low-cost, eco-friendly catalyst, are advantages of the present protocol for the synthesis of triaryl pyridines.