The general procedure for the synthesis of (2-fluorophenyl)(4-fluorophenyl)methanone from 4-fluorophenylmagnesium bromide and o-fluorobenzoyl chloride was as follows: 2-fluorobenzoyl chloride (6 mmol, 1.0 eq.) was dissolved in 2-methyltetrahydrofuran (15 mL) and transported through the material channel A and the metering pump P1; meanwhile, 4-fluorophenylmagnesium bromide (9 mmol, 1.5 eq.) was dissolved in 2- methyltetrahydrofuran (15 mL), delivered through material channel B and metering pump P2. The two solutions were mixed in the mixing module M at a preset temperature of 25 °C and a flow rate of 1 mL/min, and then entered into the reaction module L for 1 hour. Upon completion of the reaction, the reaction solution flowed out of outlet D and was collected in 1 mol/L hydrochloric acid solution for quenching. The quenched solution was stirred, washed with saturated brine solution, dried with anhydrous sodium sulfate, concentrated and purified by column chromatography to afford the target product (2-fluorophenyl)(4-fluorophenyl)methanone.
