Ethyl trifluoroacetate → 1-(5-Bromofuran-2-yl)-4,4,4-trifluorobutane-1,3-dione

Temperatur

-78 °C

To a stirred solution of compound 43 (4.8 g, 25.4 mmol) in THF (60 mL) at −78° C., LiHMDS (38 mL, 38.1 mmol) was added dropwise and the reaction stirred −78° C. for 1 h. Ethyl 2,2,2-trifluoroacetate (4.5 g, 38.1 mmol) was then added dropwise. The reaction mixture was allowed to gradually warm to room temperature in cooling bath and stirred overnight. Solvent was removed, cold water (50 mL) was added, and the reaction mixture extracted with diethyl ether (100 mL×3). Combined organic layer was washed with brine, dried over sodium sulphate and concentrated under reduced pressure. Crude compound was washed with diethyl ether and hexane to afford compound 44 (5 g, 69%) as a white solid.

1. temperatureto gradually warm to room temperature
2. temperaturein cooling bath
3. stirringstirred overnight
4. customSolvent was removed
5. additioncold water (50 mL) was added
6. extractionthe reaction mixture extracted with diethyl ether (100 mL×3)
7. washCombined organic layer was washed with brine
8. dry with materialdried over sodium sulphate
9. concentrationconcentrated under reduced pressure
10. washCrude compound was washed with diethyl ether and hexane

ORD-Eintrag

ord-401fb6608b5e42a7a84bd757da1a8647

Quelldatensatz

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08987318B2