NiFe<sub>2</sub>O<sub>4</sub>@SiO<sub>2</sub>–PPA Nanoparticle: A Green Nanocatalyst for the Synthesis of β-Acetamido Ketones

<p>In this work, silica coated magnetic nanoparticles of modified polyphosphoric acid (NiFe<sub>2</sub>O<sub>4</sub>@SiO<sub>2</sub>–PPA deigned as NFS–PPA) represent as a reusable and green catalyst for one-pot four-component synthesis of β-acetamido ketones at room temperature under solvent-free conditions. This catalyst was synthesized and characterized by X-ray diffractions, transmission electron microscopy, scanning electron microscopy and vibrating sample magnetometry. The magnetic catalyst can be easily removed by a simple magnet and reused up to five times without any loss of its high catalytic activity. In addition to facility, this protocol enhances product purity and promises economic and also environmental profits.</p>