General procedure for the synthesis of 2-fluoro-5-aminoacetophenone from 1-(2-fluoro-5-nitrophenyl)ethanone: 1-(2-fluoro-5-nitrophenyl)ethanone (0.3 g, 1.64 mmol), iron powder (0.27 g, 4.92 mmol), ammonium chloride (0.17 g, 3.28 mmol), isopropanol (12.8 mL), and water (3.2 mL ) were mixed and reacted for 3 hours. After completion of the reaction, the insoluble precipitate was removed by filtration, the organic layer was extracted with dichloromethane, dried with anhydrous magnesium sulfate, and concentrated in vacuum to obtain a yellow oily crude product. The crude product was purified by silica gel column chromatography (eluent: ethyl acetate/hexane=1:2, Rf=0.3) to afford 2-fluoro-5-aminoacetophenone (0.19 g, 76% yield).
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