[Br:1][C:2]1[CH:8]=[CH:7][CH:6]=[CH:5][C:3]=1[NH2:4].[N+:9]([O-:12])(O)=[O:10].[C:13](OC(=O)C)(=[O:15])[CH3:14]>>[Br:1][C:2]1[CH:8]=[CH:7][CH:6]=[C:5]([N+:9]([O-:12])=[O:10])[C:3]=1[NH:4][C:13](=[O:15])[CH3:14]To a solution of 2-bromoaniline (XC) (50 g, 0.29 mol, 1 eq) in acetic anhydride (265 mL) was added dropwise nitric acid (fuming) (36.75 mL, 0.93 mol, 3.2 eq) at 0° C. and then stirred at that temperature, when the starting material was consumed, the mixture was filtered, the filtrate was poured into ice water. The aqueous phase was basified with aqueous solution of sodium bicarbonate to pH=7, then the mixture was extracted with EtOAc (30 mL×3). The organic layers were combined, dried and concentrated in vacuo to give the N-(2-bromo-6-nitrophenyl)acetamide (XCI) (12.6 g, 48.6 mmol, 16.7% yield) as a white solid. 1H NMR (DMSO-d6, 400 MHz) δ ppm 2.06 (s, 3H), 7.43 (t, J=8 Hz, 1H), 7.94 (d, J=8 Hz, 1H), 8.05 (d, J=8 Hz, 1H); ESIMS found for C8H7BrN2O3 m/z 259 (M+H).
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