METHOD FOR THE PREPARATION OF CITALOPRAM

摘要

A method for the preparation of citalopram is described comprising reaction of a compound of Formula (IV) wherein R1 is H or C1-6alkylcarbonyl successively with a Grignard reagent of 4-halogen-fluorophenyl and a Grignard reagent of 3- halogen-N,N-dimethylpropylamine, effecting ring closure of the resulting compound of Formula (VI) and converting the resulting 1,3-dihydroisobenzofur an compound to the corresponding 5-cyano derivative, i.e. citalopram.