3.0 g of 4-chloro-3-methylacetophenone, 4.35 g of 3′,5′-dichloro-2,2,2-trifluoroacetophenone, 30 ml of 1,2-dichloroethane, 2.46 g of potassium carbonate and 0.18 g of triethylamine were fed and the mixture was refluxed by heating for 16 hours. The reaction solution was cooled to room temperature, and separated by adding 200 ml of ethyl acetate and iced water. The organic phase was washed with diluted hydrochloric acid and saturated saline, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (eluent is a mixed liquid of hexane:ethyl acetate=9:1) to obtain 6.2 g of 1-(4-chloro-3-methylphenyl)-3-(3,5-dichlorophenyl)-4,4,4-trifluoro-2-buten-1-one as brown liquid.
