Highly efficient and reusable hydrogel-supported nano-palladium catalyst: Evaluation for Suzuki–Miyaura reaction in water

Ligand-free, palladium-supported, poly(N-isopropylacrylamide-co-potassium methacrylate) [poly(NIPA-co-PMA)] hydrogel nanocomposite with different comonomer ratios were synthesized. The developed hydrogel–palladium composites were characterized by SEM, TEM, UV–vis DRS and XRD. The catalytic performance of these hydrogel–palladium nanocomposites was examined for Suzuki–Miyaura cross-coupling reaction of aryl halides with arylboronic acids in an aqueous medium. The hydrogel with comonomer ratio of 8.8:1.6 mmol of NIPA:PMA exhibited optimum catalytic activity, which can be effectively reused 5–6 times without loss of catalytic activity.

Graphical abstractA facile and simple approach was followed to synthesize poly(N-isopropylacrylamide-co-potassium methacrylate) hydrogel–palladium nanocomposites (Pd@GEL). Among the composite gels with variable PMA contents, Pd@GEL5 (PMA 1.6 mmol) exhibited best gel integrity, and optimum Pd and water uptakes. It was tested for the catalytic performance in Suzuki–Miyaura reaction. The catalyst was reusable 5–6 times without loss in its activity. Figure optionsDownload full-size imageDownload as PowerPoint slide