反应详情

Add magnesium sulfate (30.23 g, 251.10 mmol) to (R)-2-amino-3-benzyloxypropan-1-ol (12.30 g, 67.87 mmol) and 1,1-bis-(2,2-dimethylpropoxy)-propan-2-one (23.45 g, 101.80 mmol) in tetrahydrofuran (100 mL) at room temperature and stir for 2 hours. Filter and concentrate. Dissolve in methanol (200 mL) and cool in an ice water bath. Add sodium cyanoborohydride (8.53 g, 135.73 mmol) and then acetic acid (4.08 g, 67.87 mmol) dropwise. Warm to room temperature, stir 2 hours and concentrate to −50 mL. Dilute with ethyl acetate (˜200 mL) and add water (˜50 ml) followed by 1 N sodium hydroxide (˜200 mL). Stir 20 minutes and dilute with saturated aqueous sodium chloride. Dry (sodium sulfate), filter and concentrate to give the title compounds.

1. filtrationFilter
2. concentrationconcentrate
3. dissolutionDissolve in methanol (200 mL)
4. temperaturecool in an ice water bath
5. stirringstir 2 hours
6. concentrationconcentrate to −50 mL
7. additionDilute with ethyl acetate (˜200 mL)
8. additionadd water (˜50 ml)
9. stirringStir 20 minutes
10. additiondilute with saturated aqueous sodium chloride
11. dry with materialDry (sodium sulfate)
12. filtrationfilter
13. concentrationconcentrate