Polyethyleneimine-modified superparamagnetic Fe۳O۴nanoparticles: An efficient, reusable and water tolerancenanocatalyst.

A novel magnetically immobilized polyethyleneimine (PEI) fabricated by covalently anchoring on silica coatedFe۳O۴ nanoparticles (PEI@Si-MNPs) was prepared. The synthesized catalyst was characterized by Fouriertransform infrared (FT-IR), thermogravimetric analysis (TGA), X-ray powder diffraction (XRD), transmissionelectron microscopy (TEM) and vibrating sample magnetometry (VSM). The immobilized PEI was shown to bean efficient heterogeneous catalyst for the synthesis of spiro-oxindole, benzopyranes and chromene derivativesvia multi-component reaction (MCR), in water as a green solvent. The catalyst is readily recovered by simplemagnetic decantation and can be recycled several times with no significant loss of catalytic activity.

کلیدواژه ها:

Polyethyleneimine (PEI) ، Magnetic Nanoparticle ، benzopyranes ، Surface functionalization