A process for preparing a 1-aryl-4-(arylethyl)piperazine of the formula (I) ##STR1## by reacting a 1-arylpiperazine of the formula (II) ##STR2## with an aromatic olefin of the formula (III) in an inert solvent in the presence of at least one basic catalyst, where in the formulae (I) to (III) Ar and Ar' independently of one another are an aryl radical, selected from the group of the fused and unfused C.sub.6 -C.sub.22 -aromatics and the fused or unfused C.sub.5 -C.sub.22 -heteroaromatics which have at least one nitrogen, oxygen or sulfur atom in the ring; and R.sub.1 and R.sub.2 independently of one another are a hydrogen atom, a C.sub.1 -C.sub.8 -alkyl radical or an aryl radical Ar.
The invention relates to compounds of the formula I ##STR00001## wherein the variables are as defined in the claims. The compounds are useful in the treatment of a disease where a D4 receptor and/or a 5-HT.sub.2A receptor is implicated.
