反应详情

温度

-78 °C

To a stirred solution of 0.50 g (2.1 mmol) of benzyl (2-oxo-1,3-oxazolidin-3-yl)acetate from step A above in 15 mL of anhydrous THF at −78° C. under an atmosphere of nitrogen was added 1.2 mL (2.4 mmol) of a 2.0 M solution of lithium diisopropylamide in anhydrous THF. The resulting yellow solution was stirred for 15 min at −78° C. and then 0.0360 g (2.55 mmol) of iodomethane was added. The resulting mixture was stirred for 2 h with gradual warming to ambient temperature then quenched with a saturated aqueous ammonium chloride solution. The aqueous phase was extracted with ethyl acetate (3×20 mL) and the combined organics were washed with brine, dried over magnesium sulfate, filtered and evaporated to dryness in vacuo. The crude residue was purified by silica gel chromatography eluting with 40% ethyl acetate in hexanes to afford the title compound as a clear gum 0.37 g (70%). LC-MS: m/z (ES) 250 (MH)+.

1. stirringThe resulting mixture was stirred for 2 h
2. temperaturewith gradual warming to ambient temperature
3. customthen quenched with a saturated aqueous ammonium chloride solution
4. extractionThe aqueous phase was extracted with ethyl acetate (3×20 mL)
5. washthe combined organics were washed with brine
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. customevaporated to dryness in vacuo
9. customThe crude residue was purified by silica gel chromatography
10. washeluting with 40% ethyl acetate in hexanes