[Br:1][C:2]1[CH:12]=[CH:11][C:5]([CH:6]=[CH:7][N+:8]([O-])=O)=[C:4]([F:13])[CH:3]=1>C1COCC1>[Br:1][C:2]1[CH:12]=[CH:11][C:5]([CH2:6][CH2:7][NH2:8])=[C:4]([F:13])[CH:3]=14-Bromo-2-fluoronitro styrene (1 equivalent) in THF (0.2 M) was cooled to 0° C. and treated with 1.0 M BH3 in THF (5 equivalents). The reaction was heated to reflux overnight. The reaction was cooled to 0° C. and quenched with H2O then 1 N HCl until a pH of about 2 was achieved. The reaction was stirred for 30 minutes at room temperature and then extracted with ether (3×). The aqueous layer was made basic with 5% NaOH solution. The aqueous layer was then extracted into ether (3×). The combined organic layers were washed with brine, dried over Na2SO4, filtered, and concentrated to give crude 2-(4-bromo-2-fluorophenyl)ethylamine. Purification by flash chromatography eluting with 2%-5%-10% MeOH/CH2Cl2 gradients containing 1% concentrated ammonia afforded the desired compound. MS m/z 219.8 (M+H).
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