Patent ID: 6365747
Filing Date: 2002-04-02
Classification: A61P,C07D

Abstract:
A method for the preparation of citalopram or any of its enantiomers and acid addition salts thereof comprising treatment of a compound of formula IV wherein X is O or S;R1-R2 pendently selected from hydrogen and C1-6 alkyl, or R1 and R2 together form a C2-5 alkylene chain thereby forming a spiro-ring; R3 is selected from hydrogen and C1-6 alkyl, R4 is selected from hydrogen, C16 alkyl, a carboxy group or a precursor group therefore, or R3 and R4 together form a C2-5 alkylene chain thereby forming a spiro-ring, with a dehydration agent or alternatively where X is S, thermally cleaving the thiazoline ring, or treatment in presence of a radical initiator, to form citalopram having the formula and thereafter optionally converting the free base or an acid addition salt thereof thus obtained to a pharmaceutically acceptable salt thereof.