Reaktion #214350
ord-4fa835e709e2426385a04f0a6c8137c7
Reaktionsgleichung
Edukte
Reagenzien
Keine
Reaktionsbedingungen
Detaillierte Bedingungen
See reaction.notes.procedure_details.
Aufarbeitung
- 1TemperaturThe mixture was heated
- 2Temperaturunder reflux for 5 hours
- 3Temperaturcooled
- 4Filtrationfiltered an the filtrate
- 5Sonstigewas evaporated to dryness
- 6SonstigeThe residue which crystallized from methanol (0,5% pyridine)
- 7Sonstigegave
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.