[CH2:1]([N:8]1[C:13]([CH3:14])=[CH:12][C:11]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)=[CH:10][C:9]1=[O:23])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(O)(=O)C.C([O-])(=O)C.[Na+].[Br:33]Br>O>[CH2:1]([N:8]1[C:13]([CH3:14])=[CH:12][C:11]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)=[C:10]([Br:33])[C:9]1=[O:23])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1The product from example 35, 1-benzyl-4-(benzyloxy)-6-methylpyridin-2(1H)-one (4.2 mmol, 1.3 g), acetic acid (50 mL), and sodium acetate (5.0 mmol, 0.41 g) were stirred at room temperature. Bromine (4.2 mmol, 0.67 g) was added drop wise with stirring. After ½ hour, water (100 mL) was added and the mixture was extracted with ethyl acetate (3×50 mL). The combined organic extracts were washed with saturated aqueous sodium bicarbonate solution and brine. After drying over magnesium sulfate and concentrating, the mixture was purified by flash column chromatography eluting with ethyl acetate:hexanes (1:2). The appropriate fractions were concentrated to yield a light oil. (1.0 g, 62%): 1H NMR (DMSO-d6/300 MHz) 7.4-7.0 (m, 10H), 6.5 (s, 1H), 5.29 (s, 2H), 5.27 (s, 2H), 2.2 (s, 3H). ESHRMS m/z 384.057 (M+H, C20H18NO2Br requires 384.060).
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