反应详情

Sodium nitrate (4.93 g, 57.98 mmol) was added portionwise to (S)-2-amino-4-methoxybutanoic acid (CAS no. 3311-01-1) (3.86 g, 29.0 mmol) in acetic acid (88 mL) at room temperature (with intermittent cooling with an ice bath to keep the temperature near to room temperature). Once the addition was complete, the mixture was left to stir at room temperature for 24 h. The solvent was then removed in vacuo, the residue was dissolved in ether (250 mL), and the ethereal solution was washed with water (3×100 mL). The organic layer was extracted with saturated NaHCO3 solution (3×100 mL). The aqueous extracts were then acidified with 2N HCl and extracted with ether (3×100 mL). The combined organic layers were dried (MgSO4) and reduced in vacuo to give crude (S)-2-acetoxy-4-methoxybutanoic acid (0.600 g, 11.8%) which was used without further purification.

1. customnear to room temperature
2. additionOnce the addition
3. waitthe mixture was left
4. customThe solvent was then removed in vacuo
5. dissolutionthe residue was dissolved in ether (250 mL)
6. washthe ethereal solution was washed with water (3×100 mL)
7. extractionThe organic layer was extracted with saturated NaHCO3 solution (3×100 mL)
8. extractionextracted with ether (3×100 mL)
9. dry with materialThe combined organic layers were dried (MgSO4)