反应详情

To a suspension of sodium hydride 60% in oil (4.48 mmoles) in a mixture of THF/DMF (2.7 ml/0.45 ml) at 0° C. under an inert atmosphere there is added, dropwise, a solution of 1,3-oxazolidin-2-one (24.1 mmoles) in a mixture of THF/DMF (71 ml/5.6 ml) over 30 minutes. After stirring for 1 hour, a solution of the compound obtained in Step A (26.5 mmoles) in a mixture of THF/DMF (56 ml/11.2 ml) is added over 1.5 hours, maintaining the temperature below 10° C. Stirring is maintained for 1.5 hours. Water (12 ml) is slowly added to the reaction mixture and then the THF is removed under reduced pressure. The reaction mixture is diluted with saturated aqueous NaCl solution and then extracted 3 times with 100 ml of AcOEt. The organic phases are combined, washed with saturated aqueous NaCl solution and then dried with MgSO4. After filtration, the organic phase is evaporated to dryness. The residue is purified on silica gel (SiO2, eluant CH2Cl2) to yield the title product which is used directly in the next Step.

1. additionis added
2. additionis added over 1.5 hours
3. temperaturemaintaining the temperature below 10° C
4. stirringStirring
5. temperatureis maintained for 1.5 hours
6. customthe THF is removed under reduced pressure
7. additionThe reaction mixture is diluted with saturated aqueous NaCl solution
8. extractionextracted 3 times with 100 ml of AcOEt
9. washwashed with saturated aqueous NaCl solution
10. dry with materialdried with MgSO4
11. filtrationAfter filtration
12. customthe organic phase is evaporated to dryness
13. customThe residue is purified on silica gel (SiO2, eluant CH2Cl2)