5-Iodo-2-chlorobenzoic acid (20.0 g, 0.071 mol) was added to a solution of 2.0 M oxalyl chloride in dichloromethane (39 ml, 0.078 mol), stirred for suspension, and then 8 drops of DMF solution was added dropwise. The solution was clarified after the reaction was carried out for 3 hours. The solvent was spin-dried on a rotary evaporator, and then 15 ml of methylene chloride was added. After spin-drying, add 30 ml of dichloromethane, stir, cool to 0-5 ° C, add fluorobenzene (7. lg, 0.074 mol), add anhydrous aluminum trichloride (9.9 g, 0.074 mol) in batches, control The temperature is not more than 5 °C, after the completion of the addition, stirring is continued at 4 ° C for 1 h, the reaction is quenched on the ice-water mixture, the organic phase is separated, and the aqueous phase is extracted with dichloromethane. The phase was washed twice with 1 mol/L hydrochloric acid, once with water, and twice with 1 mol/L NaOH solution. The mixture was washed twice with saturated sodium chloride and dried over anhydrous sodium sulfate. Drain filtration, spin dry solvent to obtain oil after column chromatography, 20. 1g (78.6percent) of a white solid (2-Chloro-5-iodophenyl)(4-fluorophenyl)methanone was obtained.