PURPOSE: To prepare the titled compound useful as an antitussive, by simple and economical means, in high yield, by reacting 1-(2-phenyl-2-alkoxyethyl)piperazine with an acetal and a propiophenone compound.

CONSTITUTION: The 1,4-disubstitued piperazine of formula IV is prepared by reacting the 1-substituted piperazine of formulaI(R is alkyl) with the acetal of formula II (R1 and R2 are alkyl, aryl or aralkyl, or may be bonded together to form alkylene) and the phenyl ketone of formula III (R3 is H, halogen, alkyl or alkoxy) pref. in the presence of a solvent, at a temperature pref. between room temperature and the boiling point of the reaction system. The reaction solvent is, e.g. alcohols, benzene, toluene, xylene, diethyl ether, dioxane, tetrahydrofuran, methyl acetate, ethylene glycol, etc.