By condensation of 2,4-dichloro-alpha-(1-imidazolyl)propiophenone (I) with 2-(4-chlorophenoxy)ethyl bromide (II) by means of NaH in HMPT (hexamethylphosphotriamide) or by means of NaOH tetrabutylammonium hydroxide in toluene water, and separation of the (Z)- and (E)-isomers by crystallization of the corresponding nitrates.