Process for the preparation of citalopram and its salts, comprising reacting magnesium (5-cyano-2-(4-fluorobenzoyl)phenyl)methanolate bromide with 3-N,N-dimethylaminopropyl magnesium halide in a mixture of solvents, obtaining a diol intermediate in the form of its acid addition salt, and reacting the acid addition salt with sulfuric acid in an aqueous medium.
A substantially pure (S)-4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)benzonitrile intermediate for preparing escitalopram is prepared by:
a) combining racemic (±)-4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)benzonitrile with (−)-di-p-toluoyltartaric acid, in a solvent;
b) separating a solid phase comprising a salt of (−)-di-p-toluyltartaric acid with (R)-4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)benzonitrile enantiomer, and a liquid phase comprising a salt of (−)-di-p-toluoyltartaric acid with (S)-4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxy-butyl]-3-(hydroxymethyl)benzonitrile enantiomer;
c) reacting the liquid phase with a base and isolating enantiomerically enriched (S)-4-[4-(dimethylamino)-1-(4′-fluorophenyl)-1-hydroxybutyl]-3-(hydroxymethyl)benzonitrile enantiomer;
d) combining enantiomerically enriched (S)-enantiomer obtained in c) with (+)-di-p-toluoyltartaric acid, in a solvent; and
e) reacting a precipitate from d) with a base.
制备埃司西酞普兰的高纯度(S)-4-[4-(二甲氨基)-1-(4'-氟苯基)-1-羟基丁基]-3-(羟甲基)苯甲腈中间体的方法如下:
a) 在溶剂中将外消旋的(±)-4-[4-(二甲氨基)-1-(4'-氟苯基)-1-羟基丁基]-3-(羟甲基)苯甲腈与(-)-二对甲苯酰酒石酸结合;
b) 分离含有(-)-二对甲苯酰酒石酸盐的固相,其中包括(R)-4-[4-(二甲氨基)-1-(4'-氟苯基)-1-羟基丁基]-3-(羟甲基)苯甲腈对映体,以及含有(-)-二对甲苯酰酒石酸盐的液相,其中包括(S)-4-[4-(二甲氨基)-1-(4'-氟苯基)-1-羟基丁基]-3-(羟甲基)苯甲腈对映体;
c) 用碱反应液相,并分离对映体富集的(S)-4-[4-(二甲氨基)-1-(4'-氟苯基)-1-羟基丁基]-3-(羟甲基)苯甲腈对映体;
d) 在溶剂中将对映体富集的(S)-对映体与(+)-二对甲苯酰酒石酸结合;
e) 用碱反应从d)中得到的沉淀。