Reaktion #1342703

ord-06acae8a1b5a4158b3f7d4b686e66eae

Lösungsmittel

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    TemperaturCooled
  2. 2
    Sonstigereaction in an ice bath to +18° C
  3. 3
    Sonstigethe internal temperature<20° C
  4. 4
    TemperaturCooled to 15° C
  5. 5
    workup.ADDITIONAdded contents of addition funnel dropwise
  6. 6
    TemperaturWarmed to room temperature
  7. 7
    workup.STIRRINGStirred 1.5 hours
  8. 8
    ExtraktionExtracted three times with ethyl acetate
  9. 9
    Waschenwashed
  10. 10
    Trocknenbrine, dried with anhydrous magnesium sulfate
  11. 11
    Filtrationfiltered

Vorschrift

A 500 mL 3-neck round bottom flask under nitrogen was charged with Boc-L-4-hydroxyproline (Chem Impex) (2.00 g, 8.65 mmol) and DMSO (80 ml). Attached an addition funnel containing a solution of the product of Step 1 (1.758 g, 8.65 mmol) in DMSO (10 ml). Cooled reaction in an ice bath to +18° C. Added potassium-t-butoxide (2.91 g, 25.9 mmol) slowly keeping the internal temperature<20° C. Stirred 45 minutes at room temperature. Cooled to 15° C. Added contents of addition funnel dropwise. Warmed to room temperature. Stirred 1.5 hours. Poured into 2.5% potassium bisulfate. Extracted three times with ethyl acetate, washed combined organic portions with water then brine, dried with anhydrous magnesium sulfate, filtered and rotary evaporated filtrate to give the title compound as a white foam. (3.58 g, 8.65 mmol, 100% yield). LCMS (ES+) m/z 415.3 (M+H)+.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08461107B2uspto-grants-2013_06