[Li+].C[Si]([N-][Si](C)(C)C)(C)C.[NH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.[Br:18][C:19]1[C:24](F)=[C:23]([N+:26]([O-:28])=[O:27])[CH:22]=[CH:21][C:20]=1[F:29]>C1COCC1>[Br:18][C:19]1[C:20]([F:29])=[CH:21][CH:22]=[C:23]([N+:26]([O-:28])=[O:27])[C:24]=1[NH:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1LiHMDS (1.0M in THF, 16.8 mL, 16.8 mmol) was added dropwise to a stirred solution of aniline (821 mg, 8.80 mmol) in anhydrous THF (20 mL) under a nitrogen atmosphere at −78° C. After 10 min stirring at −78° C., a solution of 2-bromo-1,3-difluoro-4-nitrobenzene (2.0 g, 8.40 mmol) in THF (10 mL) was added and stirring at −78° C. was continued for 30 min. The reaction mixture was quenched by addition of water and extracted with EtOAc (×3). The combined organic fractions were washed with brine, dried (MgSO4), concentrated in vacuo and the resulting residue purified by column chromatography (Si—PCC, gradient 0-100% DCM in cyclohexane) to afford the title compound (2.4 g, 91%). 1H NMR (CDCl3, 400 MHz): δ 8.48 (1H, s), 8.19-7.12 (1H, m), 7.33-7.25 (2H, m), 7.09 (1H, t, J=7.41 Hz), 6.93-6.83 (3H, m).
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