79-04-9

95-50-1

42981-08-8

General method: 1,2-Dichlorobenzene (50 g, 340 mmol) was mixed with anhydrous AlCl3 (45.354 g, 340 mmol) and heated to 70 °C. The mixture was then heated to 70 °C. The reaction was followed by the addition of 3-chloropropionyl chloride (47.506 g, 374 mmol). Subsequently, 3-chloropropionyl chloride (47.506 g, 374 mmol) was added slowly and dropwise. The reaction mixture was stirred continuously at 70 °C for 6 hours. After the reaction was completed, it was cooled to room temperature and diluted with dichloromethane (300 mL). The diluted mixture was slowly poured into ice water (200 mL) and stirred for 30 minutes. The organic layer was separated, washed with brine, dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: EtOAc/hexane=1/50, V/V) to afford the target product 2,3',4'-trichloroacetophenone (compound 2a) as a white solid (64.6 g, 80% yield).