Patent ID: 7709662

Claim:
A method of manufacturing (S)-N-methyl-3-(1-naphthyloxy)-3-(2-thienyl)propylamine of formula I or its pharmaceutically acceptable salt, comprising (RS)-N,N-dimethyl-3-(1-naphthyloxy)-3-(2-thienyl)propylamine of formula III is reacted with an optically active acid, after which a crystallization is carried out of that diastereoisomer which yields, in reaction with an inorganic or organic base, (S)-N,N-dimethyl-3-(1-naphthyloxy)-3-(2-thienyl)propylamine of formula (S)-III, which is then demethylated using alkylchloroformates, followed by hydrolysis and optional conversion of the compound of formula I to its salt.