Magnetic nanoparticles as a catalyst vehicle for simple and easy recycling

The surface of magnetic ferrite nanoparticles (CoFe2O4) was coated with a Rh-based cationic complex, [Rh(cod)(eta(6)-benzoic acid)]BF4, to make them homogeneously dispersable and thermodynamically stable without an excess amount of surface capping molecules in normal organic solvents. Since magnetic nanoparticles themselves have strong magnetic properties and could be considered as a nanometer-sized solid support for the surface-anchored Rh-based catalyst, the ferrite nanoparticle-supported Rh catalyst showed very effective catalytic activity toward the hydroformylation reaction of olefins and could be easily recovered from the reaction mixture by magnetic decantation to be used for subsequent reactions.