[CH3:1][O:2][C:3]1[C:4]([N+:10]([O-:12])=[O:11])=[C:5](N)[CH:6]=[CH:7][CH:8]=1.N([O-])=O.[Na+].C([O-])(O)=O.[Na+].[BrH:22]>O>[Br:22][C:5]1[CH:6]=[CH:7][CH:8]=[C:3]([O:2][CH3:1])[C:4]=1[N+:10]([O-:12])=[O:11]3-Methoxy-2-nitro-phenylamine (360 mg, 2.14 mmol) was dissolved in HBr (48%, 4.8 mL) at 0° C. A solution of sodium nitrite (0.16 g, 2.40 mmol) in water (360 μL) was added dropwise to the stirred solution over one hour period while the temperature was maintained at 0° C. Then a cold (0° C.) freshly prepared solution of CuBr2 (from CuSO4.5H2O (1.0 g) and HBr (48%, 1.0 mL) mixed 30 min. at room temperature to give a dark purple solution) was added at 0° C. to the reaction mixture. The resulting solution was stirred at 0° C. for 3 hours and at room temperature for 2 days. The reaction mixture was poured onto ice and neutralized carefully with a saturated solution of NaHCO3. The aqueous phase was extracted with AcOEt. The resulting organic phase was washed with brine, dried over MgSO4, filtered and evaporated to yield 482 mg (2.08 mmol, 97%) of 1-bromo-3-methoxy-2-nitrobenzene as an orange solid.
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