Uses
(4-Chloro-3-nitrophenyl)(4-fluorophenyl)methanone (cas# 31431-16-0) is a useful chemical in the manufacturing process for flubendazole, an anthelmintic that is used in dogs and cats to treat parasites and worms.
Synthesis
To the reaction flask was added 1800 g of fluorobenzene and 2250 g of aluminum trichloride, and pre-cooled 3-nitro-4-chlorobenzoyl chloride solution was slowly added dropwise to the reaction flask, controlling the reaction temperature to be at 25-30 °C. After the dropwise addition was completed, the reaction was continued at this temperature for 2 hours. Upon completion of the reaction, the reaction mixture was slowly added dropwise to 10 kg of dilute hydrochloric acid at a concentration of 3.0%, ensuring that the temperature did not exceed 65 °C during this process. After stirring for 0.5 hours, the mixture was allowed to stand to allow the mixture to stratify, separating and retaining the lower organic phase. The organic phase was washed with 600 g of a 10% concentration aqueous sodium carbonate solution. Subsequently, the solvent o-dichlorobenzene was removed by distillation under reduced pressure, 5400 g of methanol was added to the residue and the mixture was heated to reflux. After stirring for 0.5 h, the mixture was cooled to promote crystallization. After filtration and drying, 2387 g of 4-chloro-3-nitro-4'-fluorodiphenyl ketone was obtained with a purity of 98.7% and an overall yield of 95.7%.
