Reacción #448863

Ecuación de reacción

11β-fluoro-estra-4,6-diene-3,17-dione

1-bromo-6-chlorohexane

lithium bromide

magnesium

→

7α-(6-chlorohexyl)-11β-fluoro-estr-4-ene-3,17-dione

Disolventes

acetic acid

THF

THF

1,3-dimethyl-3,4,5,6-tetrahydro-(1H)-pyrimidin-2-one

trimethyl-chlorosilane

THF

THF

1,3-dimethyl-3,4,5,6-tetrahydro-(1H)-pyrimidin-2-one

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONthe remaining solution is added in drops in such a way that the internal temperature
2. 2
   Otrodoes not exceed 35° C
3. 3
   Otroclimbs to 40° C
4. 4
   TemperaturaWithout cooling
5. 5
   OtroA clear solution is obtained
6. 6
   workup.ADDITIONwhich is added in drops to the Grignard solution that
7. 7
   Temperaturais cooled to -40° C
8. 8
   workup.STIRRINGThen, it is stirred for 30 more minutes at -30° C.
9. 9
   Otrodoes not exceed -40° C
10. 10
    workup.STIRRINGIt is stirred for 1 hour cold
11. 11
    Otrothe cooling bath is removed
12. 12
    workup.STIRRINGstirred for 1 more hour at room temperature
13. 13
    workup.ADDITIONthe reaction mixture is added to 1.51 of water
14. 14
    workup.ADDITIONdiluted with the same amount of ethyl acetate
15. 15
    Otrothe precipitate is separated on Celite
16. 16
    Extracciónthe aqueous phase is extracted 3 times with ethyl acetate
17. 17
    Lavadowashed with sodium bicarbonate and common salt solution
18. 18
    Otrodried on magnesium sulfate
19. 19
    Concentraciónconcentrated by evaporation in a vacuum
20. 20
    OtroAfter the crude product is chromatographed on silica gel with a hexane-ethyl acetate gradient

Procedimiento

First 30 ml of a solution that consists of 41 ml of 1-bromo-6-chlorohexane in 270 ml of THF is added to a suspension of 6.8 g of magnesium chips in 100 ml of THF. After the reaction starts, the remaining solution is added in drops in such a way that the internal temperature does not exceed 35° C. In a second flask, 48.1 g of lithium bromide is added to a suspension of 26.4 g of copper(I) iodide in 120 ml of THF at 0° C., whereby the internal temperature climbs to 40° C. Without cooling, 46.4 ml of 1,3-dimethyl-3,4,5,6-tetrahydro-(1H)-pyrimidin-2-one is now added and stirred for 30 minutes at 40° C. A clear solution is obtained, which is added in drops to the Grignard solution that is cooled to -40° C. Then, it is stirred for 30 more minutes at -30° C. and mixed drop by drop at -50° C. with a solution of 23.5 g of 11β-fluoro-estra-4,6-diene-3,17-dione in 230 ml of THF, 24.6 ml of 1,3-dimethyl-3,4,5,6-tetrahydro-(1H)-pyrimidin-2-one and 55 ml of trimethyl-chlorosilane in such a way that the internal temperature does not exceed -40° C. It is stirred for 1 hour cold, then 32 ml of glacial acetic acid is added in drops, the cooling bath is removed and stirred for 1 more hour at room temperature. For working-up, the reaction mixture is added to 1.51 of water, diluted with the same amount of ethyl acetate, the precipitate is separated on Celite, rewashed with ethyl acetate, the aqueous phase is extracted 3 times with ethyl acetate, washed with sodium bicarbonate and common salt solution, dried on magnesium sulfate and concentrated by evaporation in a vacuum. After the crude product is chromatographed on silica gel with a hexane-ethyl acetate gradient, 25.2 g of 7α-(6-chlorohexyl)-11β-fluoro-estr-4-ene-3,17-dione is obtained.

Fuente