The cyclization of ethyl 2-chloro-2-(4-fluorophenylhydrazono)acetate (I) with 4-(4-chloro-beta-styryl)morpholine (II) by means of triethyiamine in refluxing CHCl3 gives ethyl 4-(4-chlorophenyl)-1-(4-fluorophenyl)-5-morpholino-4,5-dihydropyrazol-3-carboxylate (III), which is treated with HCl in refluxing dioxane yielding ethyl 4-(4-chlorophenyl)-1-(4-fluorophenyl)pyrazol-3-carboxylate (IV). The reduction of (IV) with diisobutylaluminum hydride in toluene affords [4-(4-chlorophenyl)-1-(4-fluorophenyl)-3-pyrazolyl]methanol (V), which by treatment with aqueous 63% HBr at 90 C is converted to 3-(bromomethyl)-4-(4-chlorophenyl)-1-(4-fluorophenyl)pyrazole (VI). The reaction of (VI) with KCN and 18-crown-6 in hot acetonitrile affords 4-(4-chlorophenyl)-1-(4-fluorophenyl)pyrazole-3-acetonitrile (VII), which is finally hydrolyzed with NaOH in water-DMSO at 120 C.