To a solution of 1-tert-butoxycarbonyl-4-(1H-1,2,4-triazol-1-ylmethyl)piperidine (48 mg, 0.18 mmol) in dry dichloromethane (1.5 mL) was added trifluoroacetic acid (1.5 mL), and the mixture was stirred at room temperature for 30 minutes. The solvent was distilled of under reduced pressure, and the residue was dissolved in methanol (1 mL). The solvent was distilled off under reduced pressure, and the residue was dissolved in dry acetonitrile (1.5 mL). To the solution were added 1-acetyl-N-(3-chlorophenyl)-N-(3-chloropropyl)-4-piperidinecarboxamide (50 mg, 0.14 mmol), potassium carbonate (77 mg, 0.56 mmol) and potassium iodide (23 mg, 0.14 mmol), and the mixture was stirred at 80° C. for 5 hours. The mixture was cooled to room temperature, and to the mixture was added water. The mixture was saturated with sodium chloride, and extracted three times with ethyl acetate (2 mL). The extracts were combined and concentrated under reduced pressure. The concentrate was purified by using HPLC to give the titled compound as a colorless oily substance (49.1 mg, 58%).
