反应详情

To ethanol (188 ml, 3.24 mol) was added at 0° C. acetyl chloride (46 ml, 0.65 mol). The mixture was stirred at the same temperature for 30 minutes and added to tert-butyl(3S)-3-{[(benzyloxy)carbonyl]amino}-4-hydroxybutanoate (10.0 g, 32.3 mmol) in ethanol (20 ml). The mixture was stirred overnight. After removal of the solvent, the residue was dissolved in ethyl acetate and the solution was washed with a saturated aqueous sodium hydrogen carbonate solution and then a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate. The organic solvent was removed under reduced pressure, and the residue was purified by silica gel chromatography to give ethyl (3S)-3-{[(benzyloxy)carbonyl]amino}-4-hydroxybutanoate (2.92 g, 32%) with a lactone compound, benzyl (3S)-5-oxotetrahydro-3-furanylcarbamate (4.24 g, 56%) as by-product.

1. stirringThe mixture was stirred overnight
2. customAfter removal of the solvent
3. dissolutionthe residue was dissolved in ethyl acetate
4. washthe solution was washed with a saturated aqueous sodium hydrogen carbonate solution
5. dry with materiala saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate
6. customThe organic solvent was removed under reduced pressure
7. customthe residue was purified by silica gel chromatography