Ruthenium nanoparticles prepared from ruthenium dioxide precursor: Highly active catalyst for hydrogenation of arenes under mild conditions

The hydrogenation of benzene and benzene derivatives was studied using Ru(0) nanoparticles prepared by a very simple method based on the in situ reduction of the commercially available precursor ruthenium dioxide under mild conditions (75 °C and hydrogen pressure 4 atm) in imidazolium ionic liquids. Total turnovers (TTO) of 2700 mol/mol Ru were obtained for the conversion of benzene to cyclohexane under solventless conditions and TTO of 1200 mol/mol Ru were observed under ionic liquid biphasic conditions. When corrected for exposed ruthenium atoms, TTO values of 7940 (solventless) and 3530 (biphasic) were calculated for benzene hydrogenation. These reaction rates are higher than those observed for Ru nanoparticles prepared from decomposition of an organometallic precursor in similar conditions. The presence of the partially hydrogenated product cyclohexene was also detected at low conversion rates.

Ru(0) nanoparticles prepared by a very simple method based on the reduction of the commercially available precursor ruthenium dioxide under mild condition are highly active catalysts for the hydrogenation of benzene. At 75 °C and 4 atm hydrogen pressure, we obtained total turnovers of 2700 and 1200 mol/mol Ru in solventless and ionic liquid biphasic conditions, respectively.Figure optionsDownload as PowerPoint slide