To a solution of 1.49 g of 4-ethylbenzaldoxime in 10 mL of N,N-dimethylformamide, 1.60 g of N-chlorosuccinimide was added and the resultant mixture was stirred at room temperature for 2 hours. Next, to the reaction mixture, 3.00 g of 3,5-bis(trifluoromethyl)-1-(1-trifluoromethylethenyl)benzene and 3.00 g of potassium hydrogen carbonate were added and the stirring of the resultant reaction mixture was continued at room temperature further for 14 hours. After the completion of the reaction, 10 mL of water was added to the reaction mixture and the resultant reaction mixture was extracted with ethyl acetate (50 mL×1). The organic phase was washed with 20 mL of water and then dehydrated and dried over saturated saline and anhydrous sodium sulfate in this order, and the solvent was distilled off under reduced pressure. To the resultant residue, hexane was added and a deposited crystal was filtered off to obtain 3.00 g of the objective substance as a white crystal.
