反应详情

90 ml of a solution of n-butyllithium in n-hexane (1.60 mol/l) (144 mmol) was added to a solution of 25.0 g of (S)-4-benzyl-2-oxazolidinone (141 mmol) in tetrahydrofuran (600 ml) under a nitrogen atmosphere and at −78° C. over 10 minutes, and the mixture was stirred at the same temperature for 20 minutes. Then, 19.0 ml of n-valeryl chloride (159 mmol) was added over 10 minutes. The mixture was stirred at the same temperature for 20 minutes and then further stirred at room temperature for three hours. 90 ml of a saturated ammonium chloride aqueous solution was added to the reaction mixture, and the mixture was further stirred at room temperature for 15 minutes. The reaction mixture was concentrated under reduced pressure and diluted with 300 ml of water, followed by extraction with methylene chloride. Then, the organic layer was washed with a saturated sodium bicarbonate aqueous solution and brine and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure to obtain 37.3 g of the crude title compound.

1. stirringThe mixture was stirred at the same temperature for 20 minutes
2. stirringfurther stirred at room temperature for three hours
3. stirringthe mixture was further stirred at room temperature for 15 minutes
4. concentrationThe reaction mixture was concentrated under reduced pressure
5. additiondiluted with 300 ml of water
6. extractionfollowed by extraction with methylene chloride
7. washThen, the organic layer was washed with a saturated sodium bicarbonate aqueous solution and brine
8. dry with materialdried over anhydrous magnesium sulfate
9. filtrationAfter filtration
10. customthe solvent was evaporated under reduced pressure