Ionic liquid supported on magnetic nanoparticles (-Fe2O3@SiO2-IL-ZnxCly) as the green catalyst for the Paal-Knorr reaction

Abstract

The ionic liquid supported on magnetic nanoparticles ( -Fe2O3@SiO2-IL-ZnxCly) was found to be an effective catalyst for the Paal–Knorr reaction. The condensation of aromatic amine and acetonylacetone under solvent-free sonication afforded the desired pyrrole derivatives in high yields. The pyrrole derivatives was isolated in yield with a environmentally friendly process. The structure of products was determined by modern methods such as nuclear magnetic resonance spectroscopy (1H and 13C NMR), high resolution mass spectrometry (HR-ESI-MS) or gas chromatography-mass spectrometry (GS-MS). Moreover, the catalyst could be easily recovered by magnetic separation and reused for five times without significant loss of the catalytic activity.