Reaktion #214350

ord-4fa835e709e2426385a04f0a6c8137c7

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    TemperaturThe mixture was heated
  2. 2
    Temperaturunder reflux for 5 hours
  3. 3
    Temperaturcooled
  4. 4
    Filtrationfiltered an the filtrate
  5. 5
    Sonstigewas evaporated to dryness
  6. 6
    SonstigeThe residue which crystallized from methanol (0,5% pyridine)
  7. 7
    Sonstigegave

Vorschrift

10 g of sulfonic acid resin (Amberlite I R120, marketed by Rohm and Haas Co.) was dehydrated by azeotropic destillation with benzene. The dry resin was suspended in 50 ml isopropenylacetate and 10 g 9β,11β-epoxy-21-acetoxy-17-hydroxy-pregna-1,4-diene-3,20-dione were added. The mixture was heated under reflux for 5 hours, cooled and filtered an the filtrate was evaporated to dryness. The residue which crystallized from methanol (0,5% pyridine) gave in high yield (9,5 grams) 3,21-diacetoxy-17-hydroxy-9β,11β-epoxy-pregna-1,3,5-triene-20-one. Melting point: 194° C., λmax 310 nm (ε5500)⟦alpha⟧sub.D in chloroform -199° C. (c=1% chloroform), νmax (cm-1) (K Br) 3450; 1765; 1740; 1725; 1655; 1625; 1590.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US04255331uspto-grants-1981_03