Organoselenium–palladium(ii) complex immobilized on functionalized magnetic nanoparticles as a promising retrievable nanocatalyst for the “phosphine-free” Heck–Mizoroki coupling reaction
Abstract
In the present study, for the first time, an air- and moisture-stable organoselenium–palladium complex immobilized on silica-coated magnetic nanoparticles was designed, synthesized and applied as a practical and retrievable catalyst in organic synthesis. The chemical nature and structure of this novel catalytic system were characterized using various techniques such as Fourier transform infrared (FT-IR) spectroscopy, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy and vibrating sample magnetometry (VSM). Subsequently, the catalytic performance of the synthesized nanocatalyst was investigated in the Heck–Mizoroki cross-coupling reaction and excellent results are obtained. The low catalyst loading, wide substrate scope, high yield, short reaction time, simple separation from the reaction mixture and importantly, the longevity of the nanocatalyst for at least five successive recycles without significant degradation in its activity are the main merits of this protocol. Above all, this work opens up attractive and interesting routes for the use of organoselenium compounds as efficient ligands for the synthesis of heterogeneous catalysts.