METHOD FOR SEPARATION OF INTERMEDIATES WHICH MAY BE USED FOR THE PREPARATION OF ESCITALOPRAM

摘要

The invention relates to a method of separating and isolating an acylated derivative of 4-[(S)-4-dimethylamino-1-(4-fluorophenyl)-1-hydroxybutyl]-3-hydroxymethylbenzonitrile by reaction of a mixture of the 4-[(S)-4-dimethylamino-1-(4-fluorophenyl)-1-hydroxy-butyl]-3-hydroxymethylbenzonitrile and an acylated derivative thereof with a compound which form a derivative of the 4-[(S)-4-dimethylamino-1-(4-fluorophenyl)-1-hydroxy-butyl]-3-hydroxymethylbenzonitrile containing a carboxylic acid group. The acylated derivative containing a carboxylic acid group precipitates once it is formed and may easily be separated from the reaction mixture.