Reacción #214350

ord-4fa835e709e2426385a04f0a6c8137c7

Ecuación de reacción

C=C(C)CC(=O)[O-]
isopropenylacetate
c1ccccc1
benzene
CC(=O)OCC(=O)[C@@]1(O)CC[C@H]2[C@@H]3CCC4=CC(=O)C=C[C@]4(C)[C@@]34O[C@H]4C[C@@]21C
9β,11β-epoxy-21-acetoxy-17-hydroxy-pregna-1,4-diene-3,20-dione
→
CC(=O)OCC(=O)[C@@]1(O)CC[C@H]2[C@@H]3CC=C4C=C(OC(C)=O)C=C[C@]4(C)[C@@]34O[C@H]4C[C@@]21C
3,21-diacetoxy-17-hydroxy-9β,11β-epoxy-pregna-1,3,5-triene-20-one

Reactantes

C=C(C)CC(=O)[O-]
isopropenylacetate
—
sulfonic acid
c1ccccc1
benzene
CC(=O)OCC(=O)[C@@]1(O)CC[C@H]2[C@@H]3CCC4=CC(=O)C=C[C@]4(C)[C@@]34O[C@H]4C[C@@]21C
9β,11β-epoxy-21-acetoxy-17-hydroxy-pregna-1,4-diene-3,20-dione

Reactivos

Ninguno

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    TemperaturaThe mixture was heated
  2. 2
    Temperaturaunder reflux for 5 hours
  3. 3
    Temperaturacooled
  4. 4
    Filtraciónfiltered an the filtrate
  5. 5
    Otrowas evaporated to dryness
  6. 6
    OtroThe residue which crystallized from methanol (0,5% pyridine)
  7. 7
    Otrogave

Procedimiento

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.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US04255331uspto-grants-1981_03