Eumelanin supported palladium nanoparticle as a heterogeneous catalyst for Suzuki cross coupling reaction in water

Abstract

Eumelanin, which is a biological pigment, is widely distributed in almonst all living organism

animals, plants, human skins and hair. The pigment has many distinctive physical and chemical properties such as broad featureless absorption, antibiotic funtion and conducting property. Eumelanin contains various functional groups like hydroxyl and carboxylic acid groups which exhibit ability to capture metal ions. Thus, eumelanin could be a good candidate as a catalyst support. We have successfully prepared eumelanin supported palladium nanoparticle catalysts from L-DOPA (L-3,4-dihydroxyphenylalanine). As expected, the eumelanin supported palladium nanoparticle catalysts (Eum@Pd NP) exhibited a good catalytic activity in Suzuki cross coupling in water. Even with aryl chlorides, the catalyst gave high yield in water.