To a 100 mL three-necked round-bottomed flask treated with an inert atmosphere under nitrogen protection was added iron powder (14 g, 250.00 mmol, 10.50 equiv), acetic acid (1.5 mL) and water (24 mL). The mixture was heated to 100 °C and then 1,2-dichloro-4-fluoro-5-nitrobenzene (5 g, 23.81 mmol, 1.00 eq.) was slowly added. The reaction mixture was stirred continuously at 100 °C for 30 min. Subsequently, the reaction solution was cooled to 10 °C using an ice-water bath and the pH was adjusted to 8-9 with saturated aqueous sodium bicarbonate. the solid insoluble material was removed by filtration, the filtrate was extracted with ether (3 x 40 mL), the organic phases were combined, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. Finally, 4.2 g (98% yield) of 4,5-dichloro-2-fluoroaniline was obtained as a white solid.
