反应详情

温度

0 °C

3,4-Dihydro-2H-pyran (90.5 ml, 1.2 eq) was added dropwise to a mixture of 4-[(R)-2-hydroxypropionyl]morpholine (132 g) and p-toluenesulfonic acid monohydrate (500 mg, 0.003 eq) in dry dichloromethane (500 ml) over a period of 15 min with stirring at 0° C. After being stirred for 30 min at 0° C., the mixture was washed with aqueous sodium bicarbonate, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. Purification of the residue by silica gel chromatography, using n-hexane: ethyl acetate (8:1)˜ethyl acetate as an eluent, gave 4-[(2R)-2-(3,4,5,6-Tetrahydro-2H-pyran-2-yloxy)propionyl]morpholine (191.6 g, 95% yield) as a pale yellow oil.

1. stirringAfter being stirred for 30 min at 0° C.
2. washthe mixture was washed with aqueous sodium bicarbonate
3. dry with materialdried over anhydrous magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. customPurification of the residue by silica gel chromatography