A mixture of 4-{[2-chloro-4-(trifluoromethyl)pyrimidin-5-yl]carbonyl}morpholine (170 mg), 2,4-dichlorophenol (112 mg), cesium carbonate (225 mg), and N,N-dimethyl formamide (2 mL) was stirred at room temperature for 15 hours, and then at 100° C. for 10 hours. To the reaction liquid was added ethyl acetate (30 mL), followed by washing with saturated brine (20 mL) and a saturated aqueous ammonium chloride solution (20 mL) in this order, the organic layer was dried over anhydrous magnesium sulfate, and then the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: chloroform-ethyl acetate) to obtain 4-{[2-(2,4-dichlorophenoxy)-4-(trifluoromethyl)pyrimidin-5-yl]carbonyl}morpholine (36 mg) as a brown oily substance.
