Reaktion #460677

ord-eacdb49e9a0246048bd884c2be364982

Lösungsmittel

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturthe reaction mixture was heated to 70° C. for 1.5 hours
  2. 2
    Temperaturcooled
  3. 3
    Einengenconcentrated in vacuo
  4. 4
    workup.ADDITIONwas added
  5. 5
    Temperaturthe reaction mixture was heated
  6. 6
    Temperaturto reflux for 2 hours
  7. 7
    Temperaturcooled
  8. 8
    workup.ADDITIONdiluted to 50 ml with EtOAc
  9. 9
    WaschenThe organic solution was washed with a 0.25N NaOH solution
  10. 10
    Extraktionextracted with 1N HCl
  11. 11
    Extraktionextracted with EtOAc
  12. 12
    Sonstigedried
  13. 13
    Filtrationfiltered
  14. 14
    Einengenconcentrated in vacuo
  15. 15
    SonstigeCrystallization from Et2O afforded pure 42 (0.62 g, 68%) as a light yellow crystalline solid, mp=95°-97°

Vorschrift

To a solution of the acid 12 (1.0 g, 2.8 mM) in benzene (25 ml) was added Et3N (0.39 ml, 2.8 mM) and diphenylphosphoryl azide (0.60 ml, 2.8 mM). After stirring overnight at room temperature, the reaction mixture was heated to 70° C. for 1.5 hours, cooled and concentrated in vacuo. Dioxane (2 ml), followed by a solution of concentrated HCl (0.3 ml) in dioxane (2 ml) was added, and the reaction mixture was heated to reflux for 2 hours, cooled and diluted to 50 ml with EtOAc. The organic solution was washed with a 0.25N NaOH solution, and extracted with 1N HCl. The extracts were combined, basified with 5N NaOH, and extracted with EtOAc, dried, filtered and concentrated in vacuo. Crystallization from Et2O afforded pure 42 (0.62 g, 68%) as a light yellow crystalline solid, mp=95°-97°. MS, m/e 327 (M+).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05164381uspto-grants-1992_11