Patent ID: 7435563

Claim:
A process for the preparation of enantiomerically pure (S)-3-methylamino-1-(thien-2-yl)propan-1-ol of the formula II-S comprising: a) reacting an enantiomer mixture of the alcohols (S)-3-hydroxy-3-thien-2-ylpropio-nitrile and (R)-3-hydroxy-3-thien-2-ylpropio-nitrile of the formulae I-S and I-R with an acylating agent in the presence of a hydrolase, obtaining a mixture of essentially unacylated alcohol of the formula I-S and essentially acylated alcohol of the formula I-R; b) separating the alcohol of the formula I-S from the mixture obtained in step a); and c) reacting the alcohol of the formula I-S with hydrogen and methylamine in the presence of a catalyst to give (S)-3-methylamino-1-(thien-2-yl)propan-1-ol of the formula II-S.