反应详情

温度

40 °C

A mixture of ampicillin trihydrate (15 g), methylaceto acetate (5.65 g), triethylamine (4.05 g) and acetone (7.5 ml) was stirred at 40° C. for 3 hours. Acetone (30 ml) and sodium bicarbonate (12.4 g) were added. 1-Bromoethyl ethyl carbonate (14.6 g) was added dropwise during 1 hour. Stirring was continued at 40° C. for 1 hour. Water (37.5 ml) was added and the reaction was stirred at 20° C. for 1 hour. Ethyl acetate (37.5 ml) was added and the phases separated. The organic phase was washed with 20% sodium chloride solution. Acetone (7.5 ml) was added and a solution of ca. 16% hydrochloric acid was added slowly until a stable pH of 2.2 was obtained. The addition takes 11/2-2 hours. The solution was dried over anhydrous sodium sulfate and filtered. Butyl acetate (45 ml) was added and the solution was evaporated in vacuo to remove most of the solvents (bath temperature 35° C.). More butyl acetate (50 ml) was added and partially distilled. The resulting slurry was cooled for several hours and filtered to give 11.6 g bacampicillin.

1. stirringStirring
2. waitwas continued at 40° C. for 1 hour
3. stirringthe reaction was stirred at 20° C. for 1 hour
4. customthe phases separated
5. washThe organic phase was washed with 20% sodium chloride solution
6. additionAcetone (7.5 ml) was added
7. additiona solution of ca. 16% hydrochloric acid was added slowly until a stable pH of 2.2
8. customwas obtained
9. additionThe addition
10. custom2-2 hours
11. dry with materialThe solution was dried over anhydrous sodium sulfate
12. filtrationfiltered
13. additionButyl acetate (45 ml) was added
14. customthe solution was evaporated in vacuo
15. customto remove most of the solvents (bath temperature 35° C.)
16. additionMore butyl acetate (50 ml) was added
17. distillationpartially distilled
18. temperatureThe resulting slurry was cooled for several hours
19. filtrationfiltered