Step 1: 2-Chloro-5-nitrophenol (20.0 g, 115.2 mmol) was dissolved in a solvent mixture of ethanol (150 mL) and water (150 mL). To this solution, iron powder (32.2 g, 576.2 mmol) and ammonium chloride (32.1 g, 599.3 mmol) were added sequentially. The reaction mixture was heated to reflux and kept for 2 hours. After completion of the reaction, it was cooled to room temperature and filtered to remove insoluble material. The filtrate was concentrated to dryness under reduced pressure. The residue was purified by fast column chromatography (eluent: hexane/ethyl acetate = 9:1) to afford 5-amino-2-chlorophenol (15.85 g, 96% yield) as a white solid.
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