Preparation of citalopram comprises the steps of: (a) converting the compound of Formula (I) to a compound of Formula (II), wherein R in Formula (I) represents a C₂ to C₅ alkylene group which may be substituted or unsubstituted, and R¹ in the compounds of Formula (II) represents a carboxylic acid group or a salt or an ester thereof; and (b) converting the compound of Formula (II) to form citalopram or a pharmaceutically acceptable salt thereof, or a direct conversion of the compound of Formula (I) to citalopram ##STR1##