[Br:1][C:2]1[CH:3]=[CH:4][C:5]([I:10])=[C:6]([CH:9]=1)[CH:7]=O.[CH2:11]([NH2:13])[CH3:12].C(O)(=O)C.C([BH3-])#N.[Na+]>CO>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([I:10])=[C:6]([CH:9]=1)[CH2:7][NH:13][CH2:11][CH3:12]To 5-bromo-2-iodo-benzaldehyde (15.0 g, 48.3 mmol) in methanol (60 mL) was added ethylamine (2.0M in methanol; 48 mL, 72.0 mmol), followed by acetic acid (3.0 mL, 53.4 mmol), and the mixture was stirred at room temperature for 30 minutes, after which a precipitate formed. Sodium cyanoborohydride (6.00 g, 95.4 mmol) was then added in 3 portions and the precipitate disappeared. The reaction was stirred at room temperature for 24 hours then quenched with saturated aqueous sodium bicarbonate. The resulting mixture was evaporated then diluted with dichloromethane and washed with water, dried over magnesium sulfate, filtered, and concentrated. The residue was purified by silica gel chromatography (0-4% methanol in dichloromethane) to give the title compound.
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