Réaction #82182

ord-f14f0b2044454b238289b5666ea71862

Conditions de réaction

Température
-30°CELSIUS
Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    workup.STIRRINGThe mixture was stirred for 90 minutes at -30° C.
  2. 2
    Températureto warm to 22° C.
  3. 3
    workup.STIRRINGstirred for an additional 18 hours
  4. 4
    Lavagethe reaction flask was washed with 10 mL of diethyl ether, which
  5. 5
    workup.ADDITIONwas added to the separatory funnel
  6. 6
    workup.STIRRINGThe mixture was shaken thoroughly
  7. 7
    Autrethe phases were separated
  8. 8
    ExtractionThe aqueous phase was extracted with diethyl ether (2×20 mL)
  9. 9
    Lavagethe combined organic phase was washed with brine
  10. 10
    Séchagedried over magnesium sulfate
  11. 11
    Autreevaporated

Mode opératoire

Sodium methoxide solution was prepared by dissolving metallic sodium (1.38 g, 60 mmol) in methanol (30 mL). This solution was diluted with anhydrous tetrahydrofuran (100 mL) and cooled to -30° C. A solution of iodine monochloride (8.97 g, 55.3 mmol) in dichloromethane (30 mL) was added dropwise to the stirred alkoxide solution. The resulting solution was stirred for 2 minutes, then the sodium salt of 1-[2-(4,6-dioxo-2,2-dimethyl-1,3-dioxan-5-yl)ethyl]-2-benzoylpyrrole (VI, 18.15 g, 50 mmol) was added as a solid. The mixture was stirred for 90 minutes at -30° C., then allowed to warm to 22° C. and stirred for an additional 18 hours. The reaction mixture was poured into 150 mL of 2% aqueous sodium sulfite solution in a separatory funnel, and the reaction flask was washed with 10 mL of diethyl ether, which was added to the separatory funnel. The mixture was shaken thoroughly, and the phases were separated. The aqueous phase was extracted with diethyl ether (2×20 mL), and the combined organic phase was washed with brine, dried over magnesium sulfate, and evaporated to afford 4-(2-benzoylpyrrol-1-yl)-2-iodobutyric acid methyl ester (IV, 18.16 g, 91.5%), identical to the material prepared by the method described above.

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US05621115uspto-grants-1997_04