Reaktion #5330

ord-d43f11dc297541b8b35b7cb26b75eb7f

Lösungsmittel

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    workup.STIRRINGthe mixture was stirred for 60 hours at 70° C
  2. 2
    SonstigeAfter removal of crystalline precipitate
  3. 3
    Filtrationby filtration
  4. 4
    Einengenthe filtrate was concentrated to dryness
  5. 5
    SonstigeThe residue was partitioned between water (1.2 liter) and ethyl acetate (350 ml)
  6. 6
    Waschenthe upper layer was washed with water (70 ml×3)
  7. 7
    SonstigeEthyl acetate was evaporated under reduced pressure
  8. 8
    workup.ADDITIONto the residue was added methanol (70 ml)
  9. 9
    FiltrationResulting crystalline precipitate was filtered off
  10. 10
    EinengenThe filtrate was concentrated to dryness under reduced pressure

Vorschrift

To a solution of hydroxylamine hydrochloride (20.85 g) in DMSO (200 ml) was added triethylamine (3.9 g) and the mixture was stirred for 30 minutes at room temperatures. To the reaction mixture was added the compound (16 g) obtained in Example (34c), and the mixture was stirred for 60 hours at 70° C. To the resultant mixture was added tetrahydrofuran (100 ml). After removal of crystalline precipitate by filtration, the filtrate was concentrated to dryness. The residue was partitioned between water (1.2 liter) and ethyl acetate (350 ml), and the upper layer was washed with water (70 ml×3). Ethyl acetate was evaporated under reduced pressure, and to the residue was added methanol (70 ml). Resulting crystalline precipitate was filtered off. The filtrate was concentrated to dryness under reduced pressure to give the title compound as a pale yellow syrup (13.0 g, 76%).

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05243054uspto-grants-1993_09