The compound (3.2 g) obtained in Example 115c and 2-amino-1-[3-(trifluoromethyl)phenyl]ethanone (2.88 g) were dissolved in dichloromethane (120 mL) and water (40 ml), and an aqueous solution (40 mL) of sodium acetate (2.46 g) was added dropwise under cooling in an ice bath. The reaction mixture was stirred at room temperature overnight, and the organic layer was separated, dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (carrier: silica gel, eluent: petroleum ether-ethyl acetate) to give the title compound (0.92 g) as a colorless solid.
