PROCESS FOR PREPARATION OF CITALOPRAM AND ENANTIOMERS

摘要

The present invention provides a process for preparation of l-[3-(dimethylamino)propyl]- l-(4-fluorophenyl)-l,3-dihydro-5-isobenzofuran carbonitrile comprising reacting a compound of formula (Iva), in the presence of a base with a compound of formula RX, wherein R is selected from alkyl, alkenyl, aryl and heteroaryl which may be optionally substituted with electron withdrawing groups and X is selected from F, Cl, Br, I, CN, Otf and ORi, wherein Tf represents trifluoromethanesulfonyl group, and R₁ is optionally substituted alkyl, Z is a cyano group or a group that may be converted to a cyano group; further wherein RX is selected such that an intermediate ether derivative, a compound of formula (Va) formed from said reaction cyclizes to a compound of formula (VI), and where Z is not a cyano group, conversion of the group Z in the compound of formula (VI) to a cyano group to form l-[3-(dimethylamino)?ropyl]-l-(4-fluoro?henyl)-l,3-dihydro-5-isobenzofuran carbonitrile. The present invention also provides novel ether compound, a compound of formula (Va) and a process for preparation thereof.