Development of an Immobilized Ketoreductase for Enzymatic (R)-1-(3,5-Bis(trifluoromethyl)phenyl)ethanol Production

The development of an immobilized ketoreductase via covalent binding on resin EC-HFA has demonstrated that it is highly active and stable in organic solvents and can be recycled and reused many times in both batch mode and flow reactor mode. (R)-1-(3,5-Bis(trifluoromethyl)phenyl)ethanol, a key chiral intermediate in the synthesis of EMEND, was synthesized in 98% yield with >99% ee using the immobilized ketoreductase in a 50% hexanes/40% IPA/10% water solvent system. The immobilized ketoreductase has also been applied to the synthesis of various chiral alcohols.