Magnetic nanoparticle supported polyoxometalate: An efficient and reusable catalyst for solvent-free synthesis of α-aminophosphonates

A new magnetically separable catalyst consisting of phosphotungstic acid (PTA) supported on imidazole functionalized silica coated cobalt ferrite nanoparticles was prepared. The synthesized catalyst was characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The immobilized phosphotungstic acid was shown to be an efficient heterogeneous catalyst for the synthesis of α-aminophosphonates under solvent-free conditions at room temperature. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (113 K)Download as PowerPoint slideHighlights► Phosphotungstic acid supported on functionalized cobalt ferrite was prepared. ► Silica coated cobalt ferrite nanoparticles were used as support. ► This composite was used as catalyst for synthesis of α-aminophosphonates. ► Economically and environmentally benign procedure. ► The catalyst can be readily separated from solution by magnetic field.