反应详情

A solution of 8.81 ml (50.6 mmol) of N,N-diisopropylethylamine and 2.09 g (20.2 mmol) of L-valinol in 10 mL of methylene chloride was added to a solution of 3.71 g (16.9 mmol) of 2-(2-furanyl)-3-oxa-1-azaspiro[4.5]dec-1-en-4-one in 100 ml of toluene, and the mixture was heated under reflux for 14 hours. The reaction solution was concentrated under reduced pressure, ethyl acetate was added to the residue, and the mixture was washed with water, a 10% aqueous potassium hydrogensulfate solution, a saturated aqueous sodium hydrogencarbonate solution and then saturated brine. The organic layer was dried with anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. Ethyl acetate was added to the residue, and the mixture was stirred overnight. The obtained crystal was collected by filtration to obtain 4.06 g (74.7%) of the title compound.

1. temperaturethe mixture was heated
2. temperatureunder reflux for 14 hours
3. concentrationThe reaction solution was concentrated under reduced pressure, ethyl acetate
4. additionwas added to the residue
5. washthe mixture was washed with water
6. dry with materialThe organic layer was dried with anhydrous sodium sulfate
7. distillationthe solvent was distilled off under reduced pressure
8. additionEthyl acetate was added to the residue
9. filtrationThe obtained crystal was collected by filtration