Iodoethane (311.9 mg, 2.000 mmol) and potassium carbonate (500.0 mg, 3.619 mmol) were added to a solution (3 ml) of 4-(2-bromo-5-hydroxybenzyl)-1-[(2-chlorophenyl)-acetyl]piperidine (400.0 mg, 0.952 mmol) in N,N-dimethylformamide, and the resulting mixture was stirred at 60° C. for 3 hours. The reaction was terminated by adding water (20 ml), followed by extraction with diethyl ether. The extract layer was washed with an aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, and then distilled under reduced pressure to remove the solvent, whereby the title compound (426.7 mg, 0.952 mmol) was quantitatively obtained.
