Poly(ethylene glycol)-stabilized Rh nanoparticles as efficient and recyclable catalysts for hydroformylation of olefins

Poly(ethylene glycol) (PEG)-stabilized Rh nanoparticles prepared by simple hydrogen reduction of RhCl ₃·3H ₂O in the presence of PEG ₄₀₀₀ (PEG with an average molecular weight of 4000 g/mol) were shown to be efficient and recyclable catalysts for hydroformylation of olefins in thermoregulated PEG biphasic system, which allows for not only an efficient homogeneous catalytic reaction, but also an easy biphasic separation and reuse of catalyst. Under the optimized conditions, the conversion of various olefins and the yield of corresponding aldehydes were ≥ 98%. The Rh nanoparticle catalyst could be separated from products by simple phase separation and recycled for twenty times without evident loss of activity.