Reaktion #502084

Reaktionsgleichung

Betulin

Jones Reagent

→

betulonic acid

Lösungsmittel

benzene

methanol

acetone

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONadded dropwise at 0° C
2. 2
   Sonstigequench with methanol (100 mL)
3. 3
   workup.STIRRINGstir for 5 minutes
4. 4
   workup.ADDITIONadd H2O (200 mL)
5. 5
   SonstigeRemove organic solvent under vacuum, and then separate the precipitate
6. 6
   Filtrationby filtration
7. 7
   WaschenWash precipitate on the
8. 8
   Filtrationfilter with cooled water
9. 9
   Sonstigedry
10. 10
    Sonstigeto obtain crude material
11. 11
    FiltrationThe solution is then filtered through a layer of aluminum oxide
12. 12
    workup.ADDITIONthe eluate is treated with an aqueous 10% KOH solution until complete precipitation
13. 13
    SonstigeThe precipitate is then separated by filtration
14. 14
    Waschenwashed with 10 mL
15. 15
    Temperaturcooled benzene
16. 16
    Sonstigedried
17. 17
    Sonstigeto obtain white solid
18. 18
    workup.ADDITIONthe solution is poured into 100 mL 15% aqueous HCL solution

Vorschrift

Starting off with Betulin (10 g) in acetone (300 mL), add freshly prepared Jones Reagent added dropwise at 0° C. Stir for 5 hours, quench with methanol (100 mL), then stir for 5 minutes and add H2O (200 mL). Remove organic solvent under vacuum, and then separate the precipitate by filtration. Wash precipitate on the filter with cooled water, and dry to obtain crude material. This dry material is to be dissolved in 30 mL benzene. The solution is then filtered through a layer of aluminum oxide and the eluate is treated with an aqueous 10% KOH solution until complete precipitation. The precipitate is then separated by filtration, washed with 10 mL cooled benzene, and dried to obtain white solid. The salt is dissolved in 30 mL methanol and the solution is poured into 100 mL 15% aqueous HCL solution. The betulonic acid (2.7 g) is obtained after the precipitate is filtered, washed with water, and dried.

Quelle