Br[C:2]1[CH:7]=[CH:6][C:5]([Br:8])=[CH:4][N:3]=1.C([Li])CCC.[O:14]1[CH2:17][C:16](=[O:18])[CH2:15]1.[Cl-].[NH4+]>C1(C)C=CC=CC=1>[Br:8][C:5]1[CH:6]=[CH:7][C:2]([C:16]2([OH:18])[CH2:17][O:14][CH2:15]2)=[N:3][CH:4]=12,5-Dibromopyridine (10 g, 35.2 mmol) is dissolved in dry toluene (200 mL) under a nitrogen atmosphere and cooled to −78° C. n-Butyllithium (2.5M in hexanes, 2.5 mL, 38.7 mmol) is added at −78° C. over 20 minutes. The reaction mixture is stirred at −78° C. for 20 minutes. Oxetane-3-one (2.79 g, 38.7 mmol) in toluene (100 mL) is added then stirred at −78° C. for 30 minutes. Saturated aqueous ammonium chloride solution (50 mL) is added. The mixture extracted with ethyl acetate (2×200 mL), separated, washed with brine solution (50 mL) and the solvent evaporated under reduced pressure. The crude material is purified using flash chromatography (35% ethyl acetate in hexane) to give the title compound (4.2 g): 1H NMR (400 MHz, DMSO-d6):δ 4.64 (2H, d), 4.87 (2H, d), 6.68 (1H, s), 7.55 (1H, d), 8.06 (1H, dd), 8.76 (1H, d).
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