To a solution of ethyl 3-(2,4-difluorophenyl)-3-oxopropionate (9 g, 39.4 mmol) in 1,2-dimethoxyethane (50 ml) was added sodium hydride (60% in oil, 1.58 g, 39.4 mmol) under ice-cooling and the mixture was stirred at room temperature for 30 min. To the reaction solution was dropwise added a solution of 4-trifluoromethylbenzyl bromide (9.43 g, 39.4 mmol) in 1,2-dimethoxyethane (50 ml) and the reaction solution was stirred at room temperature for 3 hrs. The reaction solution was poured into water (200 ml) and extracted with ethyl acetate (200 ml×2). The extract was washed with water and saturated brine, dried over anhydrous magnesium sulfate and evaporated under reduced-pressure. The residue was purified by silica gel column chromatography (toluene:hexane=1:1-toluene) and recrystallized from diisopropyl ether-hexane to give ethyl 3-(2,4-difluorophenyl)-3-oxo-2-((4-(trifluoromethyl)phenyl)methyl)propionate (11.6 g, 77%).
