Dimethyl Carbonate → 6-bromo-1H,2H,4H-pyrido(2,3-d)(1,3)oxazin-2-one

To a stirred solution of 2-amino-5-bromo-3-(hydroxymethyl)pyridine (3.0 g, 15 mmole) in methanol (30 mL) was added dimethyl carbonate (5 mL, 60 mmole) and sodium methoxide (25 wt % solution in methanol, 4 mL, 17.4 mmole). The reaction was heated at reflux for 18 hr, cooled to RT, and concentrated to dryness. The remaining residue was triturated with saturated aqueous NH4Cl (50 mL), filtered, washed with cold H2O (50 mL), and dried under vacuum to give the title compound (1.75 g, 51%) as a beige solid: LCMS (ES) m/e 229.0 (M+H)+; 1H NMR(400 MHz, DMSO-d6) δ 10.90 (s,1H), 8.31 (s,1H), 7.90 (s,1H), 5.31 (s, 2H).

1. temperatureThe reaction was heated
2. temperatureat reflux for 18 hr
3. concentrationconcentrated to dryness
4. customThe remaining residue was triturated with saturated aqueous NH4Cl (50 mL)
5. filtrationfiltered
6. washwashed with cold H2O (50 mL)
7. customdried under vacuum

ORD record

ord-f9ccd7724707424dab7963ca0440486e

Source dataset

uspto-grants-2005_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06846819B1