PROCESS FOR THE PREPARATION OF ESCITALOPRAM OR ITS ACID ADDITION SALTS

摘要

The present invention relates to Formula (I), a process for the preparation of highly pure Escitalopram or its acid addition salts which comprises: a) reacting racemic diol or its ester derivative (III) with an optically active acid and at least one solvent to get enantiomerically pure diastereomer (IIIA); b) separating the enantiomerically pure diastereomer (IIIA) from its optically active acid salt by treating it with base and followed by stereo selective cyclization; c) separating the Escitalopram base.