610-78-6

16026-77-0

Step 1. Reduction reaction: 4-chloro-3-nitrophenol (6.0 g, 34.6 mmol) and acetic acid (60 mL) were added to a 100-mL round-bottom flask equipped with a magnetic stir bar. Iron powder (325 mesh, 19.31 g, 346 mmol) was then added and the reaction mixture was heated with stirring at 100 °C for 30 min. After completion of the reaction, the mixture was cooled to room temperature and diluted with deionized water (40 mL). Step 2. Post-treatment: The diluted mixture was filtered through a diatomaceous earth pad and washed thoroughly with deionized water. The filtrate was extracted with ethyl acetate and the organic phases were combined and concentrated under reduced pressure. Step 3. Purification: Heptane (~100 mL) was added to the concentrated residue, followed by evaporation under reduced pressure to remove residual acetic acid and water, and the process was repeated. The final residue was dissolved in acetonitrile and concentrated again under reduced pressure. The resulting solid was suspended in heptane and concentrated under reduced pressure to afford 3-amino-4-chlorophenol (4.38 g, 88% yield) as a lavender to amber solid. The mass spectrum (ESI, cation mode) showed m/z 144 [M + 1].