Reaktion #336779

ord-ed51c8fd325849e8873d840053a8eec6

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Extraktionextracted with ethyl acetate
  2. 2
    WaschenThe extract is washed with water
  3. 3
    Trocknendried over sodium sulfate
  4. 4
    Einengenconcentrated
  5. 5
    workup.STIRRINGthe mixture is stirred for 30 minutes
  6. 6
    workup.STIRRINGthe mixture is stirred at -20 to -30° C. for 10 minutes and under ice cooling for 40 minutes
  7. 7
    Waschenwashed with brine
  8. 8
    Trocknendried over sodium sulfate
  9. 9
    Einengenconcentrated
  10. 10
    Waschenwashed with ether
  11. 11
    workup.DISSOLUTIONdissolved in dichloromethane
  12. 12
    Waschenwashed with 5% aqueous sodium hydrogen carbonate
  13. 13
    Trocknendried over sodium sulfate
  14. 14
    Einengenconcentrated
  15. 15
    SonstigeThe residue is purified by silica gel chromatography (toluene : ethyl acetate=2:1)

Vorschrift

To a solution of 7β-phenylacetamido-3-(1,2,3-triazol-4-ylthiomethylthio)-3-cephem-4-carboxylic acid diphenylmethyl ester (10.0 g : 15.9 mMol.) in dichloromethane (100 ml) under ice cooling are added pyridine (1.54 ml : 19.1 mMol.) and trityl chloride (5.32 g 19.1 mMol.), and the mixture is stirred at room temperature for 1 hour. The reaction mixture is mixed with 10% hydrochloric acid (2 ml), diluted with water, and extracted with ethyl acetate. The extract is washed with water, dried over sodium sulfate, and concentrated. To a solution of the residue in dichloromethane (50 ml) under ice cooling are added pyridine (2.57 ml : 31.8 mMol.) and phosphorus pentachloride (5.96 g : 28.6 mMol.), and the mixture is stirred for 30 minutes. The reaction mixture is added dropwise to a solution of 1.3-butanediol (8.6 ml : 95.9 mMol.) in dichloromethane (25 ml) at -30° C. , and the mixture is stirred at -20 to -30° C. for 10 minutes and under ice cooling for 40 minutes. The reaction mixture is mixed with water, diluted with dichloromethane, washed with brine, dried over sodium sulfate, and concentrated. The residue is pulverized with ether, washed with ether, dissolved in dichloromethane, washed with 5% aqueous sodium hydrogen carbonate, dried over sodium sulfate, and concentrated. The residue is purified by silica gel chromatography (toluene : ethyl acetate=2:1) to give 7β-amino-3-(trityl-1,2,3-triazol-4-ylthiomethylthio) -3-cephem-4- carboxylic acid diphenylmethyl ester (6.70 g : pale yellow foam. Yield: 56 %,

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05214037uspto-grants-1993_05