반응 #1008037

반응 방정식

1-(3-chloro-4-fluorophenyl)ethanone

ethyl 2,2-diethoxyacetate

LDA

→

(Z)-1-(3-Chloro-4-fluorophenyl)-4,4-diethoxy-3-hydroxybut-2-en-1-one

용매

THF

반응 조건

후처리

1. 1
   기타The resultant reaction mixture
2. 2
   기타to reach room temperature
3. 3
   기타The reaction was carefully quenched with water
4. 4
   workup.ADDITIONdiluted with EtOAc
5. 5
   기타The two layers were separated
6. 6
   추출the aq. layer was extracted with EtOAc (2×150 mL) The combined organic layer
7. 7
   세척was washed with brine
8. 8
   건조dried over anhydrous MgSO4
9. 9
   여과filtered
10. 10
    농축the filtrate was concentrated under reduced pressure
11. 11
    기타to provide a crude oil
12. 12
    기타It was purified by silica gel chromatography (1500 g Commodity column
13. 13
    세척eluting with a 10% EtOAc in hexanes)
14. 14
    workup.ADDITIONFractions containing the product
15. 15
    기타evaporated
16. 16
    기타to afford Intermediate A39A (9.97 g, 35%) as a solid

실험 절차

To a −78° C. solution of 1-(3-chloro-4-fluorophenyl)ethanone (16.25 g, 94 mmol) and ethyl 2,2-diethoxyacetate (20.73 mL, 113 mmol) in THF (392 mL) was added, dropwise, a solution of LDA (51.8 mL, 104 mmol, 2M in THF). The resultant reaction mixture was gradually allowed to reach room temperature and continued stirring for 16 h. The reaction was carefully quenched with water and diluted with EtOAc. The two layers were separated and the aq. layer was extracted with EtOAc (2×150 mL) The combined organic layer was washed with brine, dried over anhydrous MgSO4, filtered and the filtrate was concentrated under reduced pressure to provide a crude oil. It was purified by silica gel chromatography (1500 g Commodity column, eluting with a 10% EtOAc in hexanes). Fractions containing the product were combined and evaporated to afford Intermediate A39A (9.97 g, 35%) as a solid. MS(ES): m/z=257 [M-OEt]+.

출처