反应详情

To a solution of lithium hydroxide monohydrate (142 mg) in water (5 ml) was added 30 wt % aqueous solution of hydrogen peroxide (0.8 ml) at −5° C., and the mixture was stirred for 15 minutes. To this reaction mixture were sequentially added tetrahydrofuran (5 ml) and a solution of an optically active compound of 7-((R)-4-benzyl-2-oxooxazolidine-3-carbonyl)-5-(2,4-dimethoxybenzyl)-5-azaspiro[2.4]heptan-4-one (1.39 g) in tetrahydrofuran (10 ml), and the mixture was stirred for additional 1 hour. To this reaction mixture was added a solution of sodium hydrogen sulfite (815 mg) in water (5 ml), and the mixture was stirred at room temperature for 1 hour, and then extracted with ethyl acetate. This organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate only). To the resulting solid was added diisopropyl ether/ethyl acetate/n-hexane (10/1/5, 10 ml), and the mixture was stirred. A solid was collected from this suspension by filtration, and dried under reduced pressure to give the titled compound (372 mg).

1. stirringthe mixture was stirred at room temperature for 1 hour
2. extractionextracted with ethyl acetate
3. washThis organic layer was washed with a saturated aqueous solution of sodium chloride
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe resulting residue was purified by silica gel column chromatography (eluent
7. additionTo the resulting solid was added diisopropyl ether/ethyl acetate/n-hexane (10/1/5, 10 ml)
8. stirringthe mixture was stirred
9. filtrationA solid was collected from this suspension by filtration
10. customdried under reduced pressure