[CH2:1]([O:8][C:9]1[C:10]([N+:16]([O-])=O)=[N:11][C:12]([Br:15])=[CH:13][CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1>C(O)(=O)C.[Fe]>[CH2:1]([O:8][C:9]1[C:10]([NH2:16])=[N:11][C:12]([Br:15])=[CH:13][CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1A mixture of 3-benzyloxy-6-bromo-2-nitropyridine (1.6 g, 5.2 mmol) and iron powder (2.9 g, 51.8 mmol) in acetic acid (25 mL) and IMS (25 mL) was stirred at reflux for 1 hour, then cooled to room temperature and filtered though a pad of celite. The filtrate was concentrated under reduced pressure to give a residue that was partitioned between an aqueous saturated solution of sodium bicarbonate and EtOAc. The organic layer was separated and washed with water and brine, dried over Na2SO4, filtered and concentrated. The residue was purified by flash chromatography (Si—PPC, EtOAc:cyclohexane, gradient 0:100 to 40:60) to give 3-Benzyloxy-6-bromopyridin-2-ylamine as a pale yellow solid (1.0 g, 71%). 1H NMR (400 MHz, CHCl3-d): δ 7.41-7.34 (m, 5 H); 6.82 (d, J=8.1 Hz, 1 H); 6.71 (d, J=8.1 Hz, 1 H); 5.04 (s, 2 H); 4.80 (s, 2 H).
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