Polymer-supported Nano-palladium as Catalyst for Suzuki Cross-coupling Reaction in Water

A new functional resin based on Wang resin was prepared to immobilize the palladium nanoparticles. The application of the supported catalyst in the Suzuki reaction between aryl halides and arylboronic acids in water was described. The influences of the reaction conditions, such as solvent, temperature, base and the amount of the catalyst were investigated with the reaction of bromobenzene and phenylboronic acid as the model. The optimal conditions were found to be:100 ℃, n(C6H5Br)∶n(C6H5B(OH)2)∶n(WRP-Pd)∶n(K2CO3)∶n(TBAB)=1.0∶1.5∶0.005∶2.0∶0.5 and 4 h. The high yields were obtained through prolongating the reaction time when aromatic chlorides were used as substrates. The catalyst could be reused four times without significant loss in its activity by simple filtration and washing.