反应详情

温度

-20 °C

33.5 g (104.3 mmol) (−)-DIP-chloride dissolved in 195 ml THF was added under protective nitrogen gas to a mixture of 24.5 g (86.9 mmol) (E)-3-(4-amino-3-chloro-5-trifluoromethyl-phenyl)-2-hydroxy-acrylic acid, 12.1 ml (86.9 mmol) triethylamine and 98 ml THF cooled to −20° C. The reaction mixture was stirred for 1.5 hours at −20° C., brought to ambient temperature and evaporated down under reduced pressure. The residue was combined with 200 ml aqueous 1-molar sodium hydroxide solution and 150 ml TBME and stirred thoroughly. The aqueous phase was separated off, acidified with 2-molar hydrochloric acid solution with stirring and extracted twice with 250 ml TBME. The combined organic phases were filtered through activated charcoal and evaporated down under reduced pressure. The residue was heated to boiling with 500 ml of water and the hot solution was filtered clear through Celite. The precipitate formed at ambient temperature was suction filtered and dried at 65° C. in the circulating air dryer.

1. custombrought to ambient temperature
2. customevaporated down under reduced pressure
3. stirringstirred thoroughly
4. customThe aqueous phase was separated off
5. stirringwith stirring
6. extractionextracted twice with 250 ml TBME
7. filtrationThe combined organic phases were filtered through activated charcoal
8. customevaporated down under reduced pressure
9. temperatureThe residue was heated
10. filtrationthe hot solution was filtered clear through Celite
11. customThe precipitate formed at ambient temperature
12. filtrationfiltered
13. customdried at 65° C. in the circulating air dryer