Method for preparing escitalopram.

Method for preparing escitalopram. This patent discloses a method for resolution of 4- [4- (dimethylamino) -1- (4'-fluorophenyl) -1-hydroxybutyl] -3- (hydro- ximetil) -benzonitrile as a mixture of enantiomers, racemic or non racemic, in its isolated enantiomers, said method comprising the step of fractional crystallisation of 4- [4- (dimethylamino) -1- (4'-fluorophenyl) -1-hydroxybutyl ] -3- (hydroxymethyl) -benzonitrile as a salt with e- nantiomero (+) - (S, S) - or (-) - (R, R) - acid luoil-tartaric acid in a solvent system comprising 1-propanol, ethanol or acetonitrile.