A mixture of 28.7 parts of (2-bromoethyl)benzene, 34.7 parts of ethyl 4-anilinoisonipecotate, 25 parts of N,N-diethylethanamine and 162 parts of N,N-dimethylacetamide is stirred for 2h. 30 at 75°-80° C. The reaction mixture is poured onto 1000 parts of water and the product is extracted three times with 210 parts of 1,1'-oxybisethane. The combined extracts are washed twice with 200 parts of water, dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and 2% of methanol as eluent. The pure fractions are collected and the eluent is evaporated. The oily residue is crystallized from 2,2'-oxybispropane, yielding ethyl 4-(phenylamino)-1-(2-phenylethyl)-4-piperidinecarboxylate; mp. 65° C.
