Reaktion #951935

ord-c5842266d2e945e983330692d24f918e

Lösungsmittel

Reaktionsbedingungen

Temperatur
-70°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturwas slowly warmed to room temperature
  2. 2
    workup.ADDITIONThe mixture was poured
  3. 3
    Sonstigeupon evaporation of the dry ice the solvent
  4. 4
    Sonstigewas removed in vacuo
  5. 5
    Extraktionextracted with chloroform (2X)
  6. 6
    SonstigeThe organic layer was separated
  7. 7
    Einengenconcentrated in vacuo
  8. 8
    Sonstigeto afford 6.0 g
  9. 9
    Sonstigeof recovered
  10. 10
    EinengenThe aqueous layer was concentrated in vacuo and 3N HCl
  11. 11
    workup.ADDITIONwas added to the residue
  12. 12
    TemperaturThe 15 solution was cooled
  13. 13
    Sonstigea solid was obtained which
  14. 14
    Filtrationwas collected by filtration
  15. 15
    SonstigeThe solid was recrystallized from water

Vorschrift

A solution of lithium diisopropylamide (6.4 g, 0.06 mol) in THF (100 ml) under nitrogen was cooled to -70° C. and a solution of 3, 5-dichloro-2-[2-(4-morpholinyl) ethoxy]pyridine (13.0 g, 0.047 mol) in THF (10 ml) was added via syringe. The yellow/red solution was stirred for 30 minutes at -70° C. and then was slowly warmed to room temperature. The mixture was poured onto crushed dry ice/THF and upon evaporation of the dry ice the solvent was removed in vacuo. The residue was taken up in dilute ammonium hydroxide and extracted with chloroform (2X). The organic layer was separated and concentrated in vacuo to afford 6.0 g of recovered starting material. The aqueous layer was concentrated in vacuo and 3N HCl was added to the residue. The 15 solution was cooled and a solid was obtained which was collected by filtration. The solid was recrystallized from water to afford 3,5-dichloro-2-[2-(4-morpholinyl)ethoxy]pyridine-4-carboxylic acid hydrochloride as a white solid in 71% yield (based on recovered starting material), m.p. 230°-231° C. (dec.).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05563163uspto-grants-1996_10