The general procedure for the synthesis of 4-bromo-2,3-difluoroaniline using 2,3-difluoroaniline as starting material was as follows: 2,3-difluoroaniline (1 eq.) and N-bromosuccinimide (1 eq.) were dissolved in acetonitrile (1 M). The reaction mixture was stirred at 35°C for 2 hours. After completion of the reaction, the solvent was removed by distillation under reduced pressure to give the crude product. The crude product was dissolved in water and extracted with ethyl acetate. The organic phases were combined and concentrated under reduced pressure to obtain the crude product. Finally, the crude product was purified by silica gel column chromatography to afford the target compound 4-bromo-2,3-difluoroaniline in 68% yield.
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