A Novel Thermoregulated Ionic Liquid and Organic Biphasic System With Rh Nanoparticles for Olefin Hydroformylation

Abstract

A thermoregulated ionic liquid and organic biphasic system composed of quaternary ammonium-based ionic liquid N,N-dimethyl-N-(2-(2-methoxyethoxy)ethyl)-N-(2-(2-octyloxyethoxy)ethyl) ammonium methanesulfonate (1) and cyclohexane was first applied for the Rh nanoparticle catalyzed hydroformylation of olefins, which allows for not only a highly efficient homogeneous catalytic reaction, but also an easy separation and reuse of catalyst. Under the optimized conditions, various olefins could be converted completely with ≥98 % selectivity for aldehydes. After reaction, the Rh nanoparticle catalyst could be recovered by simple phase separation and reused for five times without evident loss of activity. A novel thermoregulated ionic liquid 1/cyclohexane biphasic system with ionic liquid 1-stabilized Rh nanoparticles was developed and used for the hydroformylation of olefins. The ionic liquid 1-stabilized Rh nanoparticle catalyst not only exhibited high activity and selectivity for aldehydes in the hydroformylation of olefins, but also could be separated from product by simple phase separation and reused for five times without evident loss of activity.