Ruthenium‐Catalyzed Hydroformylation of Alkenes by using Carbon Dioxide as the Carbon Monoxide Source in the Presence of Ionic Liquids

The reaction of [BMI ⋅ Cl] (BMI=1‐butyl‐3‐methylimidazolium) or [BMMI ⋅ Cl] (BMMI=3‐butyl‐1,2‐dimethylimidazolium) with Ru 3 (CO) 12 generates Ru–hydride–carbonyl–carbene species in situ that are efficient catalysts for a reverse water gas shift/hydroformylation/hydrogenation cascade reaction. The addition of H 3 PO 4 increased the catalytic activity of the first step (i.e., the hydrogenation of CO 2 to CO). Under the optimized reaction conditions [120 °C and 6.0 MPa CO 2 /H 2 (1:1) for 17 h], cyclohexene and 2,2‐disubstituted alkenes were easily functionalized to alcohols through sequential hydroformylation/carbonyl reduction.