A mixture of 10 parts of N-(2-chloroethyl)-α-phenylbenzenemethanamine hydrochloride 7 parts of 4-(4-chlorophenyl)-4-piperidinol, 10.6 parts of sodium carbonate, 0.1 parts of potassium iodide and 80 parts of 4-methyl-2-pentanone is stirred and refluxed overnight. The reaction mixture is taken up in water and the layers are separated. The aqueous phase is extracted with 4-methyl--pentanone. The combined organic phases are washed with water, dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol (96:4 by volume) as eluent. The pure fractions are collected and the eluent is evaporated. The residue is crystallized from a mixture of methylbenzene and 2,2'-oxybispropane. The product is filtered off and dried, yielding 4.5 parts of 4-(4-chlorophenyl)-1-{2-[(diphenylmethyl)amino]ethyl}-4-piperidinol; mp. 113.9° C.
