1-(4-Bromo-3-chlorophenyl)ethanone

99-90-1

3114-31-6

The general procedure for the synthesis of 4'-bromo-3'-chloroacetophenone from p-bromoacetophenone was as follows: 4-bromo-3-chloroacetophenone (Compound Va.3, where X=3-Cl, Y=H, Z=Br) was prepared. 100 g of 4-bromoacetophenone was dissolved in 250 mL of dichloromethane and slowly added dropwise at 0°C to a 600 mL solution of dichloromethane containing 133.34 g of aluminum chloride. The reaction mixture was stirred continuously for 2 hours at 0°C. Subsequently, 28.3 mL of chlorine gas bubbled pre-frozen to -75°C was passed into the reaction system at 0°C. The reaction mixture was transferred to room temperature and stirred for 12 hours, after which it was hydrolyzed. Once the phases were separated, the organic and aqueous phases were separated and the aqueous phase was extracted with dichloromethane. The organic phases were combined, dried with magnesium sulfate and the solvent was removed by evaporation under reduced pressure. The resulting residue was purified by recrystallization from hexane in 57% yield with a melting point of 80 °C.