Synthesis, Characterization, and Behavior of Hydridoruthenium Carbonyl Clusters Substituted with Functionalized Phosphines in the Presence of Hydrogen. 1. H<sub>4</sub>Ru<sub>4</sub>(CO)<sub>8</sub>[P(CH<sub>2</sub>OCOR)<sub>3</sub>]<sub>4</sub> (R = CH<sub>3</sub>−, C<sub>2</sub>H<sub>5</sub>−, (CH<sub>3</sub>)<sub>2</sub>CH−, (CH<sub>3</sub>)<sub>3</sub>C−, (<i>S</i>)-C<sub>2</sub>H<sub>5</sub>CH(CH<sub>3</sub>)−)

The synthesis and characterization of phosphines containing ester groups P(CH<sub>2</sub>OCOR)<sub>3</sub> (R = CH<sub>3</sub>−, C<sub>2</sub>H<sub>5</sub>−, (CH<sub>3</sub>)<sub>2</sub>CH−, (CH<sub>3</sub>)<sub>3</sub>C−, (<i>S</i>)-C<sub>2</sub>H<sub>5</sub>CH(CH<sub>3</sub>)−) are reported. The new hydridoruthenium complexes H<sub>4</sub>Ru<sub>4</sub>(CO)<sub>8</sub>[P(CH<sub>2</sub>OCOR)<sub>3</sub>]<sub>4</sub> (R = CH<sub>3</sub>−, C<sub>2</sub>H<sub>5</sub>−, (CH<sub>3</sub>)<sub>2</sub>CH−, (CH<sub>3</sub>)<sub>3</sub>C−, (<i>S</i>)-C<sub>2</sub>H<sub>5</sub>CH(CH<sub>3</sub>)−) were synthesized and characterized. The structure of (+)-(<i>S</i>)-H<sub>4</sub>Ru<sub>4</sub>(CO)<sub>8</sub>{P[CH<sub>2</sub>OCOCH(CH<sub>3</sub>)C<sub>2</sub>H<sub>5</sub>]<sub>3</sub>}<sub>4</sub> was determined by X-ray diffraction. The behavior of these complexes in hydrocarbon solution with hydrogen under pressure (130 atm) in the temperature range 25−130 °C has been investigated. The ester groups present in the ligand P(CH<sub>2</sub>OCOR)<sub>3</sub> are hydrogenated under mild conditions with formation of the corresponding alcohol RCH<sub>2</sub>OH.