A novel catalyst containing palladium nanoparticles supported on poly(2-hydroxyethyl methacrylate)/CMK-1: Synthesis, characterization and comparison with mesoporous silica nanocomposite

A novel catalyst containing palladium nanoparticles supported on poly(2-hydroxyethyl methacrylate)/CMK-1 (Pd-PHEMA/CMK-1) was prepared, and its application was investigated as a heterogeneous catalyst in Heck coupling reaction. PHEMA/CMK-1 was prepared by in situ polymerization method and used as a support for palladium nanoparticles obtained through the reduction of palladium acetate by hydrazine hydrate. The structural and morphological characterizations of Pd-PHEMA/CMK-1 nanocomposite were carried out using XRD, FT-IR, BET, TGA, XPS, UV–vis, SEM and TEM techniques. This catalytic system exhibited good activity in cross-coupling reactions of aryl iodides, bromides and also chlorides with olefinic compounds in Mizoraki–Heck reactions in short reaction time and high yields. The catalytic activity of this purely organic hybrid catalyst was compared with Pd-PHEMA/MCM-48 to clarify the advantages of mesoporous carbon on mesoporous silica as support. The results showed that the activity and reusability of Pd-PHEMA/CMK-1 was much higher than Pd-PHEMA/MCM48 in Heck reaction.

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► Pd-PHEMA/CMK-1 nanocomposite was prepared as a novel heterogeneous catalyst.
► CMK-1 acted as an ideal support for Pd-poly(2-hydroxyethyl methacrylate).
► The nanocomposite showed reasonable activity for Heck reaction in water.
► Pd-PHEMA/CMK-1 showed higher thermal stability than Pd-PHEMA/MCM-48.