METHOD FOR THE PREPARATION OF (S)-2-ACETYLTHIO-3-PHENYLPROPIONIC ACID

摘要

Method for the preparation of (S)-2-acetylthio-3-phenylpropionic acid, wherein (R)-2-bromo-3-phenylpropionic acid is contacted with thioacetic acid and an organic base, for example triethylamine. Preferably the base is metered to a mixture of (R)-2-bromo-3-phenylpropionic acid and thioacetic acid at a temperature between -10 DEG C and +30 DEG C. (R)-2-bromo-3-phenylpropionic acid is preferably prepared starting from D-phenylalanine, sodium nitrite, HBr and a bromide salt, in an aqueous solution at a temperature between -10 and 30 DEG C, and subsequently without isolation converted into (S)-2-acetylthio-3-phenylpropionic acid. The (S)-2-acetylthio-3-phenylpropionic acid obtained can be used in the preparation of pharmaceuticals, in particular ACE inhibitor such as Omapatrilat.