Reaktion #796134

ord-33ea9cfa767c4500b4bb9ae9138be4f1

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    workup.ADDITIONwas added in portions over 10 min
  2. 2
    TemperaturThe solution was then heated
  3. 3
    Temperaturto reflux for 4 h
  4. 4
    Temperaturcooled
  5. 5
    ExtraktionThe solution was extracted with ether (2×200 mL)
  6. 6
    Sonstigethe combined organic layer was dried
  7. 7
    Einengenconcentrated
  8. 8
    Sonstigeto give an orange oil
  9. 9
    TemperaturThe solution was heated
  10. 10
    Temperaturto reflux for 2 h
  11. 11
    Temperaturcooled
  12. 12
    SonstigeThe aldehyde precipitated
  13. 13
    Filtrationwas collected by filtration
  14. 14
    SonstigeRecrystallization from MeOH/H2O

Vorschrift

The product from Step 1 (7.0 g, 18.7 mmol) was dissolved in acetonitrile (200 mL) and stirred at ambient temperature while ceric ammonium nitrate (32 g, 58 mmol) in H2O (60 mL) was added in portions over 10 min. The solution was then heated to reflux for 4 h, cooled, and diluted with H2O (200 mL). The solution was extracted with ether (2×200 mL), and the combined organic layer was dried and concentrated to give an orange oil. This material was dissolved in dioxane (40 mL) and treated with a solution of potassium hydroxide (KOH; 5 g, 90 mmol) in H2O (20 mL). The solution was heated to reflux for 2 h, then cooled and diluted with H2O (100 mL). The aldehyde precipitated and was collected by filtration. Recrystallization from MeOH/H2O gave the pure aldehyde as a white solid (2.2 g, 30%): mp 137-144° C.; 1H NMR (300 MHz, CDCl3) δ 10.1 (s, 1H), 8.65 (s, 1H), 8.40 (d, J=8.4 Hz, 2H), 8.0 (d, J=8.4 Hz, 2H), 7.85 (d, J=9 Hz, 2H), 7.45 (d, J=9 Hz, 2H); ESIMS m/z 384.2 (M+H).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US09179681B2uspto-grants-2015_11