[Br:1][C:2]1[C:7]([F:8])=[CH:6][C:5]([OH:9])=[C:4]([N+:10]([O-])=O)[CH:3]=1.[Cl-].[NH4+]>CO.C1COCC1.[Zn]>[NH2:10][C:4]1[CH:3]=[C:2]([Br:1])[C:7]([F:8])=[CH:6][C:5]=1[OH:9]To a solution of 4-bromo-5-fluoro-2-nitrophenol (40.0 g, 169 mmol) in MeOH (250 mL) and THF (250 mL) was added zinc powder (91.0 g, 1700 mmol) and ammonium chloride (111.0 g, 1700 mmol) and the reaction mixture was stirred at ambient temperature overnight. The reaction mixture was filtered and the filtrate was concentrated in vacuo. The residue was washed with cold water to give 2-amino-4-bromo-5-fluorophenol (38.0 g, crude) which was used in the next step directly without further purification. 1H NMR (DMSO-d6, 400 MHz): δ 9.82 (br s, 1H), δ 6.76 (d, J=7.2 Hz, 1H), 6.60 (d, J=10.0 Hz, 1H), 4.65 (br s, 2H).
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