Asymmetric hydration of ortho- or para-substituted styrenes catalyzed by biopolymer–metal complex wool–Pd

A biopolymer complex wool–Pd is found to be efficient catalyst for asymmetric hydration of ortho- or para-substituted styrenes with good to high enantioselectivity by simple and clean process under mild conditions. Chemical and optical yield are affected by some parameters, such as the Pd content in wool–Pd, reaction time, reaction temperature, amount of oxalic acid and water/ethanol. After several-time use of the complex, the chemical and optical yields of the products have no significant changes. Obviously, the methods provide an alternative way to produce chiral benzyl-alcohols by use of asymmetric hydration of ortho- or para-substituted styrenes catalyzed by biopolymer–metal complex wool–Pd.