Patent ID: 7790436

Claim:
A process for preparing optically active (1S)-3-chloro-1-(2-thienyl)propan-1-ol having formula (I) comprising (1) reducing 3-chloro-1-(2-thienyl)propan-1-one having formula (II) to said optically active (1 S)-3-chloro-1-(2-thienyl)propan-1-ol having formula (I) with an alcohol dehydrogenase from the Thermoanaerobacter genus in the presence of a cofactor; and (2) isolating said 3-chloro-1-(2-thienyl)propan-1-one having formula (II) formed in substantially enantiomerically pure form; wherein said reduction is conducted in a medium comprising said 3-chloro-1-(2-thienyl) propan-1-one having formula (II).