PALLADIUM NANOPARTICLES STABILIZED IN AROMATIC POLYMERIC ENVIRONMENT – HIGHLY ACTIVE LIGANDLESS CATALYSTS OF SUZUKI CROSS-COUPLING

Abstract

This work is devoted to the study of influence of the type of polymeric matrix of hyper-crosslinked polystyrene on the formation of catalytically active palladium nanoparticles using palladium acetate as a precursor. It was shown that the use of nonfunctionalized hyper-crosslinked polystyrene as a support allows formation of palladium nanoparticles of larger diameter (4-10 nm) than in the case of the polymer functionalized with amino groups. However, this catalyst exhibits higher activity in the Suzuki cross-coupling reaction between 4-bromoanisole and phenylboronic acid. For the most active catalyst, the influence of the reaction temperature, solvent composition and the nature of base were studied. Moreover, the study of the influence of the aryl halide nature revealed that the use of competing substrates allows achieving 100 % conversion for 4 minutes of 4-iodoanisole in the presence of 4-bromoanisole.

Keywords

• suzuki cross-coupling
• palladium
• catalyst
• nanoparticles
• hyper-crosslinked polystyrene