A new poly(N–heterocyclic carbene Pd complex) immobilized on nano silica: An efficient and reusable catalyst for Suzuki–Miyaura, Sonogashira and Heck–Mizoroki C‒C coupling reactions

Abstract

In the present study, the catalytic activity of a new poly (N‒heterocyclic carbene PdII complex) immobilized on silica nanoparticles, (PdII–NHCs)n@nSiO2 was studied in the Suzuki–Miyaura, Sonogashira and Heck–Mizoroki reactions of different aryl halides with phenylboronic acid, phenylacetylene and styrene, respectively. The (PdII–NHCs)n@nSiO2 was applied as a highly effecient heterogeneous catalyst for C‒C coupling reactions. The catalyst was characterized by FT–IR and UV–vis spectroscopic techniques, thermogravimetric analysis (TGA), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE–SEM) and inductively coupled plasma optical emission spectrometry (ICP–OES). Also, the catalytic activity did not deteriorate after eight run, and the catalyst can be separated and recovered easily by taking it out of the reaction solution.