Rhodium nanoparticles as catalysts in the hydroformylation of 1-dodecene and their recycling in thermomorphic solvent systems

Rhodium nanoparticles of about 3nm in size were provided in stabilizing polar solvents. These nanoparticles were used in hydroformylation reactions of higher alkenes; 1-dodecene was used as a model substance. With a metal/substrate ratio of 1:1000, a 97% yield of aldehydes was achieved and an n/iso ratio of 72:28 was obtained. The addition of the ligand biphephos decelerated the reaction, but high n/iso ratios of up to 96:4 were achieved. For the first time, an effective catalyst recycling of these long-term stable nanoparticles in a thermomorphic multicomponent solvent (TMS) system was performed. The catalyst phase was recycled for three runs without any evident loss in activity. TEM images proved that after the recycling runs rhodium nanoparticles were still the active catalyst.