Biguanidine-functionalized chitosan to immobilize palladium nanoparticles as a novel, efficient and recyclable heterogeneous nanocatalyst for Suzuki-Miyaura coupling reactions

Biguanidine-functionalized chitosan was synthesized and combined with palladium nanoparticles to yield a recyclable, environmentally benign, heterogeneous catalytic system for the Suzuki-Miyaura C-C coupling reaction. The catalyst was characterized using various techniques. The catalyst was used in Suzuki cross-coupling reactions of various aryl halides, including less reactive chlorobenzenes, with phenylboronic acid to give biaryls without any additive or ligand. A reusability test demonstrated that the catalyst was highly efficient even after six runs. Solid-phase poisoning and leaching tests indicated that the catalyst has a heterogeneous nature. Copyright (c) 2016 John Wiley & Sons, Ltd.