MnFe2O4 magnetic nanoparticles modified with chitosan polymeric and phosphotungstic acid as a novel and highly effective green nanocatalyst for regio- and stereoselective synthesis of functionalized oxazolidin-2-ones.

Abstract

A novel magnetically recoverable acid nanocatalyst, MnFe2O4/chitosan/phosphotungstic acid (MnFe2O4@CS@PTA), was successfully synthesized. The synthesized nanoparticle was studied as the heterogenous nanocatalyst to prepare the functionalized oxazolidin-2-ones as versatile chiral synthons in asymmetrically synthesizing the compounds with biological activity through the reaction of α-epoxyketones with urea and thiourea. This new procedure has notable advantages such as excellent yields, green reaction conditions, and short reaction time. In addition, the excellent catalytic performance in protic solvent and the easy preparation, thermal stability and separation of the catalyst make it a good heterogeneous system and a useful alternative to other heterogeneous catalysts. Perhaps, the synthesized MnFe2O4@CS@PTA is a hopeful catalytic substance for mass fine chemicals production. The structure and composition of the nanocomposite was performed by different methods and analyzed by Infrared Spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FE-SEM), Thermo-Gravimetric Analysis (TGA), X-ray Diffraction (XRD) Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM) and Brunauere Emmette Teller (BET).