Biomacromolecule supported N-heterocyclic carbene-palladium(II) as a novel catalyst for Suzuki–Miyaura and Mizoroki–Heck cross-coupling reactions (Pre-print)

Abstract

The field of catalysis is ever flourishing to meet the challenges faced in our day-to-day needs keeping in mind the environmental concerns. In line with this quest, a new N-heterocyclic carbene-palladium(II) complex grafted on cellulose, a naturally available biomacromolecule from agricultural waste sugarcane bagasse (Cellu@NHC-Pd) was synthesized as a heterogeneous catalyst. The facile multistep synthesis was achieved using low-cost chemicals and mild reaction conditions. The characterization of the Cellu@NHC-Pd heterogeneous catalyst by various analytical techniques such as FT-IR, FE-SEM, EDS, HR-TEM, TG/DTA, ICP-OES and p-XRD confirmed its structure, morphology, thermal stability and chemical composition. The Cellu@NHC-Pd heterogeneous catalyst was successfully investigated for its catalytic ability in Suzuki–Miyaura and Mizoroki–Heck cross-coupling reactions under green reaction medium at ambient temperature. The heterogeneous catalyst was examined for its catalytic effectiveness in the cross-coupling reactions for various parameters like solvent, base, temperature, time and catalyst loading. Additionally, the developed heterogeneous catalyst showed very good tolerance to a variety of functional groups. Being heterogeneous, the catalyst could be easily recovered by simple filtration. The Cellu@NHC-Pd heterogeneous catalyst can be additionally probed for its catalytic excellence in other applications.