Chitosan decorated Fe3O4 nanoparticles as a magnetic catalyst in the synthesis of phenytoin derivatives†
Abstract
In the present work, Fe3O4 nanoparticles were synthesized by the chemical coprecipitation process. Subsequently, the synthesized nanoparticles were modified with chitosan by a simple method and characterized by X-ray diffractometry (XRD), Fourier transform infrared spectrophotometry (FT-IR), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Then, phenytoin derivatives were catalyzed by magnetic Fe3O4–chitosan nanoparticles. Fe3O4–chitosan nanoparticles were found to be a recoverable organocatalyst for the efficient synthesis of 5,5-diphenylhydantoins and 5,5-diphenyl-2-thiohydantoins from substituted benzils and urea or thiourea derivatives. The nanocatalyst could be recovered easily under a magnetic field for reuse, and considerable loss of its catalytic activity was not observed after reuse in seven consecutive runs.