Supported Pd NPs over polydopamine modified-ordered mesoporous carbon (CMK-3) as an efficient and recyclable nanocatalyst for oxidative esterification of arylaldehydes

Abstract

The high surface area carbonaceous materials have been proven as an outstanding biodegradable and biocompatible material as support in heterogeneous catalysis for immobilizing active metal species. In this research work, a hitherto unreported novel material has been synthesized based on surface functionalized CMK-3 mesoporous carbon upon which the in situ prepared Pd nanoparticles (NPs) are immobilized following a simple, green and inexpensive procedure. The covalently bonded polydopamine moieties were exploited as the natural and safe reducing agents in pursuing the green reduction of Pd ions anchored over the surface. The as synthesized nanomaterial was characterized by advanced techniques like EDS, elemental mapping, TEM, SEM, XRD and ICP-OES. Subsequently, catalytic activity of this heterogeneous material CMK-3@PDA/Pd was assessed in the oxidative esterification of a range of arylaldehydes with methanol with excellent efficiency producing very good yields. Mild reaction condition in synthesis of catalyst, simple workup, unparallel catalytic activity with excellent yields, and very good reusability are the advantages of this method.