Reaktion #303245

ord-e4445a29e7334c2c9615d8c29e353459

Lösungsmittel

Reaktionsbedingungen

Temperatur
-78°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturmaintaining the temperature below −75° C
  2. 2
    Temperaturwhile maintaining the temperature below −75° C
  3. 3
    workup.STIRRINGThe mixture was stirred at −78° C. for 3 hours
  4. 4
    Temperaturto warm slowly to room temperature overnight
  5. 5
    SonstigeThe mixture was quenched with sat. aq. NH4Cl
  6. 6
    Extraktionextracted 3 times with EtOAc
  7. 7
    Waschenwashed with brine
  8. 8
    Trocknendried over MgSO4
  9. 9
    Einengenconcentrated

Vorschrift

To a solution of 1-tert-butyl 4-ethyl piperidine-1,4-dicarboxylate (2.0 g, 7.8 mmol) in THF (70 mL) at −78° C. was added dropwise LDA over 8 minutes, maintaining the temperature below −75° C. The mixture was stirred at −78° C. for 1 hour. 1-Chloromethoxy-2-methoxy-ethane (0.97 g. 7.8 mmol) was added dropwise while maintaining the temperature below −75° C. The mixture was stirred at −78° C. for 3 hours, and then allowed to warm slowly to room temperature overnight. The mixture was quenched with sat. aq. NH4Cl and extracted 3 times with EtOAc. The organics were combined, washed with brine, dried over MgSO4, and concentrated. Silica gel chromatography (10-20% ethyl acetate:hexanes) gave the title compound in 67% yield. MS (ES+) [M+H]+=346.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08193202B2uspto-grants-2012_06