Réaction #93686

Équation de réaction

Toluene

methanol

trimethylphosphite

6-Methylene-16-phenylsulfonylmethylpregna-4,16-diene-3,20-dione

6-Methylene-16-(phenylsulfinylmethyl)pregna-4,16-diene-3,20-dione

→

title compound

17α-Hydroxy-6,16-dimethylenepregn-4-ene-3,20-dione

Solvants

Ethyl acetate

water

Conditions de réaction

Traitement

1. 1
   Autrethe sealed vial was plunged into a hot oil bath with a bath
2. 2
   Autrethe reaction
3. 3
   AutreThe reaction mixture is transferred to a separatory funnel
4. 4
   Lavageis washed with water (2×10 ml)
5. 5
   ExtractionThe aqueous portion is back-extracted with toluene/ethyl acetate
6. 6
   AutreAfter the phases are separated
7. 7
   Filtrationthe organic phase is filtered through sodium sulfate
8. 8
   Concentrationthe filtrate is concentrated under reduced pressure to a volume of about 8 ml
9. 9
   workup.WAITto sit at 20°-25° for approximately 1/2 hr
10. 10
    LavageThe resulting crystals are washed down into a flask with toluene (2 ml)
11. 11
    Températurecooled to 5° for 2 hrs
12. 12
    workup.WAITto -20° for 48 hrs
13. 13
    AutreThe crystals were collected with toluene (-20°)
14. 14
    Séchagewith hexane three times and dried under nitrogen

Mode opératoire

6-Methylene-16-phenylsulfonylmethylpregna-4,16-diene-3,20-dione (Example 6, 2.0 g) is placed in a 30-ml vial under nitrogen. Toluene (20 ml), methanol (2.89 ml), TEA (0.181 ml) and trimethylphosphite 1.02 ml) are added. After 1 hr at 20°-25°, the sealed vial was plunged into a hot oil bath with a bath temperature of 90° which is stirred at 90° for 4 hrs, at which time TLC shows the reaction to be essentially complete. The reaction mixture is transferred to a separatory funnel and water (10 ml) is added. Ethyl acetate (10 ml) is added to the organic mixture, which is washed with water (2×10 ml). The aqueous portion is back-extracted with toluene/ethyl acetate: 1/1. After the phases are separated, the organic phase is filtered through sodium sulfate and the filtrate is concentrated under reduced pressure to a volume of about 8 ml. This concentrate is permitted to sit at 20°-25° for approximately 1/2 hr. The resulting crystals are washed down into a flask with toluene (2 ml) and cooled to 5° for 2 hrs, then to -20° for 48 hrs. The crystals were collected with toluene (-20°), then with hexane three times and dried under nitrogen to yield the title compound.

Source