Catalytic Activity of Bis-phosphine Ruthenium(II)−Arene Compounds: Chemoselective Hydrogenation and Mechanistic Insights

Bis-phosphine ruthenium(II)−arene complexes have been found to be highly active and chemoselective catalysts for the hydrogenation of aldehydes in the presence of olefinic bonds. Mechanistic studies, including comparisons with a structural analogue, reactions of an isolated hydride complex, base poisoning experiments, and a computational analysis, help rationalize the preferential hydrogenation of CO bonds, which is suggested to proceed via an ionic outer-sphere mechanism.