Water → 8-Chloro-1H-pyrido[2,3-B][1,4]oxazin-2(3H)-one

3-amino-4-chloro-pyridin-2-ol (650 mg, 4.49 mmol) was dissolved in anhydrous N,N-dimethyl formamide (22 ml) under nitrogen atmosphere, and chloroacetyl chloride solution (0.394 ml, 4.94 mmol) was added thereto dropwise at room temperature and stirred for 30 minutes. Potassium carbonate (1.55 g, 11.24 mmol) was added thereto dropwise at room temperature, and the reaction mixture was heated to 1000 and stirred for 18 hours. The reaction mixture was cooled to room temperature and water was added to quench the reaction, and the organic layer was extracted with ethyl acetate. The combined organic layer was washed with water and saturated saline solution, dried over anhydrous sodium sulfate (Na2SO4), filtered and evaporated under reduced pressure. The residue was recrystallized from dichloromethane and diisopropyl ether to obtain white solid (608 mg, 73%).

1. temperaturedropwise at room temperature, and the reaction mixture was heated to 1000
2. stirringstirred for 18 hours
3. temperatureThe reaction mixture was cooled to room temperature
4. customto quench
5. customthe reaction
6. extractionthe organic layer was extracted with ethyl acetate
7. washThe combined organic layer was washed with water and saturated saline solution
8. dry with materialdried over anhydrous sodium sulfate (Na2SO4)
9. filtrationfiltered
10. customevaporated under reduced pressure
11. customThe residue was recrystallized from dichloromethane and diisopropyl ether

ORD record

ord-5785950ace3e4049a91d0294388df867

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08394792B2