Reaktion #7153

ord-bd7b4d64b7d94c7185fa396d68006275

Lösungsmittel

Reaktionsbedingungen

Temperatur
40°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturis heated
  2. 2
    WaschenThe reaction solution is washed with water
  3. 3
    Trocknenthe organic layer is dried over sodium sulfate
  4. 4
    Sonstigethe solvent is evaporated under reduced pressure
  5. 5
    workup.DISSOLUTIONThe residue is dissolved in dimethylformamide (45 ml)
  6. 6
    workup.ADDITIONis added potassium phthalimide (1.9 g)
  7. 7
    workup.STIRRINGThe mixture is stirred at 50° C. for 18 hours
  8. 8
    workup.ADDITIONThe reaction solution is poured into ice-water
  9. 9
    Extraktionthe mixture is extracted with chloroform
  10. 10
    WaschenThe extract is washed with water
  11. 11
    Sonstigethe solvent is evaporated under reduced pressure
  12. 12
    workup.DISSOLUTIONThe residue is dissolved in ethanol (50 ml)
  13. 13
    workup.ADDITIONis added hydrazine monohydrate (600 mg)
  14. 14
    Temperaturheated
  15. 15
    Temperaturunder reflux for 3 hours
  16. 16
    SonstigeThe insoluble materials are removed by filtration
  17. 17
    Einengenthe filtrate is concentrated
  18. 18
    Extraktionextracted with chloroform
  19. 19
    Waschenwashed with water
  20. 20
    Sonstigethe solvent is evaporated under reduced pressure
  21. 21
    workup.DISSOLUTIONThe residue is dissolved in chloroform (50 ml)
  22. 22
    workup.ADDITIONis added di-tert-butyl dicarbonate (4.3 g)
  23. 23
    workup.STIRRINGThe mixture is stirred at 25° C. for 18 hours
  24. 24
    Sonstigethe solvent is evaporated under reduced pressure
  25. 25
    SonstigeThe residue is purified by silica gel column chromatography (eluent: gradient from 0% to 100% hexane/ethyl acetate)

Vorschrift

A mixture of Intermediate 1 (8.4 g), 1,2-dibromethane (160 ml), 40% aqueous potassium hydroxide solution (45 ml) and 40% aqueous tetrabutylammonium hydroxide solution (4.5 ml) is heated with stirring at 40° C. for 18 hours. The reaction solution is washed with water, and the organic layer is dried over sodium sulfate, and the solvent is evaporated under reduced pressure. The residue is dissolved in dimethylformamide (45 ml), and thereto is added potassium phthalimide (1.9 g). The mixture is stirred at 50° C. for 18 hours. The reaction solution is poured into ice-water, and the mixture is extracted with chloroform. The extract is washed with water, and the solvent is evaporated under reduced pressure. The residue is dissolved in ethanol (50 ml), and thereto is added hydrazine monohydrate (600 mg), and heated under reflux for 3 hours. The insoluble materials are removed by filtration, and the filtrate is concentrated, extracted with chloroform, washed with water, and the solvent is evaporated under reduced pressure. The residue is dissolved in chloroform (50 ml) and thereto is added di-tert-butyl dicarbonate (4.3 g). The mixture is stirred at 25° C. for 18 hours, and the solvent is evaporated under reduced pressure. The residue is purified by silica gel column chromatography (eluent: gradient from 0% to 100% hexane/ethyl acetate) to give the desired compound (5.2 g).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US07084176B2uspto-grants-2006_08