Magnetic Nanoparticles Supported Copper Nanocomposite: A Highly Active Nanocatalyst for Synthesis of Benzothiazoles and Polyhydroquinolines

A novel magnetically recoverable copper nanocatalyst was fabricated via the immobilization of a copper complex on the surface of silica-coated magnetic nanoparticles modified with a novel Schiff base ligand [Fe3O4@SiO2-bis(aminopyridine)-Cu]. FT-IR spectroscopy, SEM, TEM, EDX, VSM, XRD, XPS, TGA and AAS, ICP-OES techniques were applied to characterize the structure of the as-fabricated [Fe3O4@SiO2-bis(aminopyridine)-Cu(II)] nanocomposite. TEM and SEM analysis confirmed that the typical silica shell thickness was assessed to be around 20 nm. Catalytic studies revealed that the Fe3O4@SiO2-bis(aminopyridine)-Cu(II) nanocomposite is a highly efficient and green nanocatalyst for the synthesis of benzothiazoles and polyhydroquinolines. The [Fe3O4@SiO2-bis(aminopyridine)-Cu(II)] nanocatalyst could be easily recovered by a simple magnetic separation and recycled at least 6 times without deterioration in catalytic activity.