[Br:1][C:2]1[CH:7]=[C:6]([C:8]([CH3:11])([CH3:10])[CH3:9])[CH:5]=[CH:4][C:3]=1[O:12][CH3:13].[N+:14]([O-:17])([OH:16])=[O:15]>C(OC(=O)C)(=O)C.CCOC(C)=O.C([O-])(O)=O.[Na+]>[N+:14]([O-:17])([OH:16])=[O:15].[Br:1][C:2]1[CH:7]=[C:6]([C:8]([CH3:10])([CH3:9])[CH3:11])[CH:5]=[C:4]([N+:14]([O-:16])=[O:15])[C:3]=1[O:12][CH3:13]
2-Bromo-4-tert-butylanisole (4.54 g, 18.67 mmol) was dissolved in acetic anhydride (15 mL) and the solution was cooled to 0° C. A solution of nitric acid (70%, 2.5 mL) in acetic anhydride (2.5 mL) was prepared by the dropwise addition of HNO3 (70%, 2.5 mL) to Ac2O at 0° C. The HNO3 solution was pre-cooled to 0° C., and added dropwise to the stirred solution of the 2-bromo-4-tert-butylanisole over 5 min. The mixture was stirred at 0° C. for 1 h, then allowed to warm to room temperature and stirred overnight. The reaction mixture was diluted with EtOAc (150 mL) and saturated NaHCO3 (50 mL) This mixture was then neutralized by gradual addition of solid NaHCO3 until the pH was between 7-8. The organic layer was separated, washed with brine (50 mL) and dried over anhydrous Na2SO4. The solvents were removed in vacuo, the residue was purified by column chromatography (eluting with 3:1 hexane-EtOAc) to give 2-bromo-4-tert-butyl-6-nitroanisole (2 g, 37%).
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