Asymmetric Transfer Hydrogenation of Acetophenone with 1R,2S-Aminoindanol/Pentamethylcyclopentadienylrhodium Catalyst

The chiral rhodium complex pentamethylcyclopentadienylrhodium chloride dimer combined with the ligand 1R,2S-aminoindanol provides a superior catalyst for the rapid, high-yielding asymmetric transfer hydrogenation of acetophenone with 2-propanol to produce (R)- and (S)-(1)-phenylethanol. The effects of various reaction parameters such as reaction temperature, catalyst and substrate concentration, gaseous environment, and acetone concentration on conversion and enantioselectivity were investigated. The results indicate that catalyst can be deactivated by high temperature and air atmosphere, acetone reduces the reaction rate, and enantioselectivity decreases with conversion.