反应详情

4H-pyrido[4,3-b][1,4]oxazin-3-one (4.3 g, 28 mmol) was dissolved in tetrahydrofuran (140 ml) and then cooled to 0□. 1.0M Lithium aluminum hydride dissolved in tetrahydrofuran (57 ml, 57 mmol) was added thereto dropwise. After stirring for 2 hours at room temperature, 1.4 ml of water, 2.8 ml of 10% aqueous solution of sodium hydroxide, and 4.2 ml of water were added in this order under stirring. After filtering precipitates, the filtrate was extracted with ethyl acetate. The combined organic layer was dried over anhydrous sodium sulfate (Na2SO4), filtered and evaporated under reduced pressure. The residue was purified by column chromatography on amine silica eluting with a solvent of dichloromethane. The fractions containing the product were collected and evaporated to obtain colorless liquid (3.5 g, 91%).

1. temperaturecooled to 0□
2. additionwas added
3. stirringunder stirring
4. filtrationAfter filtering
5. customprecipitates
6. extractionthe filtrate was extracted with ethyl acetate
7. dry with materialThe combined organic layer was dried over anhydrous sodium sulfate (Na2SO4)
8. filtrationfiltered
9. customevaporated under reduced pressure
10. customThe residue was purified by column chromatography on amine silica eluting with a solvent of dichloromethane
11. additionThe fractions containing the product
12. customwere collected
13. customevaporated