Patent ID: 7923575

Claim:
A process for preparing (S)-Pregabalin: comprising: a) preparing a compound of the following formula 24: wherein Ar is a C 6-10 aromatic group and R is a straight or branched C 1-4 alkyl, ester, or carboxylic acid; b) reacting the compound of formula 24 with an amidation reagent to produce a compound of the following formula 25: wherein Ar is a C 6-10 aromatic group, and R is a straight or branched C 1-4 alkyl, ester, or carboxylic acid; c) carrying out a Hoffman reaction on the compound of formula 25 to produce a compound of the following formula 26: wherein Ar is a C 6-10 aromatic group, and R is a straight or branched C 1-4 alkyl, ester, or carboxylic acid; d) reacting the compound of formula 26 with ammonia and an alkali metal to produce a compound of the following formula 27; wherein R′ is a straight or branched C 1-5 alkyl; and e) reacting the compound of formula 27 with an acid to produce (S)-Pregabalin.