palladium nanoparticles immobilized on multifunctional ‎hyperbranched polyglycerol-grafted magnetic nanoparticles as a ‎sustainable and efficient catalyst for c-c coupling reactions

this study offers an exclusive class of magnetic nanoparticles supported hyperbranched polyglycerol (mnp/hpg) that was functionalized with citric acid (mnp/hpg-ca) as a host immobilization of palladium nanoparticles. the mnp/hpg-ca/pd catalyst was fully characterized using some different techniques such as thermogravimetric analysis (tga), x-ray diffraction (xrd), transmission electron microscopy (tem), scanning electron microscopy (sem), energy-dispersive x-ray spectroscopy (edx), inductively coupled plasma (icp) and x-ray photoelectron spectroscopy (xps). the new catalytic system showed high activity for the suzuki–miyaura cross-coupling and heck reaction under mild and green conditions. besides, the mnp/hpg-ca/pd was found to be a convenient catalyst for copper-free sonogashira coupling reaction in water as a green solvent at room temperature. moreover, the catalyst could be recovered easily and reused several times without significant loss of reactivity. ease of preparation, oxygen insensitive, phosphine-free, air- and moisture-stable, and high reusability of this immobilized palladium catalyst are the noteworthy advantages of this catalytic system.