Potassium Carbonate → 6-Bromo-2H-pyrido[3,2-B][1,4]oxazin-3(4H)-one
反応式
C[O:2][C:3](=O)[CH2:4][O:5][C:6]1[C:7]([NH2:13])=[N:8][C:9]([Br:12])=[CH:10][CH:11]=1.C([O-])([O-])=O.[K+].[K+]>CO>[Br:12][C:9]1[CH:10]=[CH:11][C:6]2[O:5][CH2:4][C:3](=[O:2])[NH:13][C:7]=2[N:8]=1参加物
4
反応条件
- 温度
- 70 °C
実験手順
(2-Amino-6-bromopyridin-3-yloxy)acetic acid methyl ester (4.0 g, 15 mmol) was dissolved in MeOH (40 mL). K2CO3 (3.0 g, 22 mmol) was added and the reaction was stirred at 70° C. for 1 hour. Then, the solvent was removed under reduced pressure and the resulting slurry was suspended in dichloromethane (DCM) and washed with H2O and then brine. The organic layer was dried (Na2SO4) and the product was precipitated from DCM/Et2O to give 6-bromo-4H-pyrido[3,2-b][1,4]oxazin-3-one. Yield 1.9 g (8.3 mmol, 55%). LCMS (ESI): calc. C7H5BrN2O2=228, 230; obs. M+H=229, 231.