Patent ID: 6566540
Filing Date: 2003-05-20
Classification: A61P,C07D

Abstract:
A method for the preparation of S-citalopram, comprising the steps ofa) deprotecting a compound of Formula IV â€ƒwherein R is C1-6 alkyl, acyl, C1-6 alkylsulfonyl or arylsulfonyl; b) reacting the resulting compound of Formula VIII â€ƒwith 3-(N,N-dimethylamino)propyl magnesium halide, to prepare the racemic compound of Formula III â€ƒfollowed by c) separation of the R and S enantiomers of the compound of formula III; d) ring closure of the S-enantiomer of the compound of formula III and isolation of S-citalopram or a salt thereof.