反应详情

温度

25 °C

L-Serine (20.00 g, 190.3 mmol) was dissolved in water, and aqueous sodium hydroxide was added to adjust the pH of the solution to about 8.5 while maintaining the temperature at about 25° C. Benzyl chloroformate (36.0 g, 211.0 mmol) was added while the pH was maintained between 8.3 and 8.5 by the addition of aqueous sodium hydroxide and the temperature was maintained at about 30° C. The mixture was stirred for about 2 hours. The reaction mixture was extracted with methylene chloride. The phases were separated, and the pH of the aqueous phase was adjusted to about 7 with concentrated hydrochloric acid. The aqueous phase was heated to about 40° C. under low vacuum to remove any residual methylene chloride. Water was added and the aqueous solution was heated to about 60° C. The pH was adjusted to about 2 with concentrated hydrochloric acid while maintaining the temperature at about 60° C. The solution was cooled to about 50° C. while stirring and seed crystals were added. With stirring, cooling was continued to about 0° C. to complete the crystallization. The product was collected and the cake was washed with cold (about 5° C.) water. The product was dried under vacuum at about 40° C. to afford carbobenzyloxy-L-serine.

1. temperaturethe temperature was maintained at about 30° C
2. extractionThe reaction mixture was extracted with methylene chloride
3. customThe phases were separated
4. temperatureThe aqueous phase was heated to about 40° C. under low vacuum
5. customto remove any residual methylene chloride
6. additionWater was added
7. temperaturethe aqueous solution was heated to about 60° C
8. temperaturewhile maintaining the temperature at about 60° C
9. temperatureThe solution was cooled to about 50° C.
10. stirringwhile stirring
11. additionseed crystals were added
12. stirringWith stirring
13. temperaturecooling
14. customwas continued to about 0° C.
15. customthe crystallization
16. customThe product was collected
17. washthe cake was washed with cold (about 5° C.) water
18. customThe product was dried under vacuum at about 40° C.