Reacción #648593

ord-cd031a5dadef4a1595b77fc1d8a0e4eb

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    Extracciónthe mixture was extracted with diethyl ether
  2. 2
    Secadothe combined organic phases were dried over sodium sulfate
  3. 3
    Filtraciónfiltered
  4. 4
    Concentraciónconcentrated
  5. 5
    workup.STIRRINGstirred at 65° C. for 4 h
  6. 6
    TemperaturaCooling
  7. 7
    Concentraciónwas followed by concentration
  8. 8
    Concentraciónagain concentrated each time
  9. 9
    workup.ADDITIONwere added
  10. 10
    workup.STIRRINGthe mixture was stirred at RT overnight
  11. 11
    Otrothe phases were separated
  12. 12
    Extraccióntwo extractions with dichloromethane
  13. 13
    Secadothe combined organic phases were dried over sodium sulfate
  14. 14
    Filtraciónfiltered
  15. 15
    Concentraciónconcentrated
  16. 16
    OtroThe crude product was purified by flash chromatography on silica gel (mobile phase: dichloromethane/methanol 9/1)

Procedimiento

6.50 g (46.7 mmol) of the compound from Example 72A were introduced into 20 ml of methanol at RT, 46.7 ml (46.7 mmol) of a 1N aqueous sodium hydroxide solution were added, and the mixture was stirred at RT for 2 h. Concentrated hydrochloric acid was then added until the pH was 2, the mixture was extracted with diethyl ether, and the combined organic phases were dried over sodium sulfate, filtered and concentrated. The residue was taken up in 8.5 ml (117 mmol) of thionyl chloride and stirred at 65° C. for 4 h. Cooling was followed by concentration, and the residue was twice taken up in diethyl ether and again concentrated each time. The residue was introduced into 17 ml of dichloromethane, 3.43 g (35.1 mmol) of N,O-dimethylhydroxylamine hydrochloride and 9.8 ml (70.3 mmol) of triethylamine were added, and the mixture was stirred at RT overnight. Water was added, the phases were separated, two extractions with dichloromethane were carried out, and the combined organic phases were dried over sodium sulfate, filtered and concentrated. The crude product was purified by flash chromatography on silica gel (mobile phase: dichloromethane/methanol 9/1) to result in 1.72 g (24% of theory) of the title compound.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US08063234B2uspto-grants-2011_11