反应详情

温度

-5 °C

To a solution of (2S,3R)-2-amino-3-benzyloxy-butyric acid (1.1 g) in 2M sulfuric acid (6.31 mL) was added dropwise over 2 h a solution of sodium nitrite (0.65 g) in water (6 mL), keeping the internal temperature of the reaction below 0° C. The reaction mixture was stirred at −5° C. for 6 h then allowed to warm to room temperature overnight. The mixture was adjusted to pH 4 with 50% aqueous sodium hydroxide then ethyl acetate was added. The mixture was stirred vigorously and acidified to pH 2 with concentrated sulfuric acid. The layers were separated and the aqueous layer extracted with further ethyl acetate (×2). The combined organic extracts were washed with saturated aqueous sodium chloride, dried (MgSO4), filtered and evaporated to give the subtitle compound as a yellow crystalline solid which was used without further purification. Yield: 0.84 g.

1. customthe internal temperature of the reaction below 0° C
2. temperatureto warm to room temperature overnight
3. stirringThe mixture was stirred vigorously
4. customThe layers were separated
5. extractionthe aqueous layer extracted with further ethyl acetate (×2)
6. washThe combined organic extracts were washed with saturated aqueous sodium chloride
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. customevaporated