Reaktion #464769

ord-7afaae95df874977b992019f7a7db2ca

Lösungsmittel

Reaktionsbedingungen

Temperatur
90°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Temperaturwas refluxed
  2. 2
    Temperaturwith heat for 4 hours
  3. 3
    workup.DISTILLATIONThe reaction mixture was distilled to dryness
  4. 4
    Waschenwashed with n-hexane several times
  5. 5
    SonstigeTo the residue obtained
  6. 6
    Sonstigeprecipitated
  7. 7
    SonstigeThe crystal obtained
  8. 8
    Filtrationto filter off undissolved substances,and
  9. 9
    Sonstigepurified by silica gel column chromatography (eluent: chloroform)

Vorschrift

A mixture of 1,2-dihydro-4-(3,4-methylenedioxyphenyl)-2-oxo-3-quinoline carboxylic acid obtained in reference example 1 (10 g, 32.3 mmol) and phosphorous oxychloride (100 ml, 1.07 mol) was refluxed with heat for 4 hours. The reaction mixture was distilled to dryness and washed with n-hexane several times. To the residue obtained was added 50 g of polyphosphoric acid, and the mixture was heated at 90° C. for 2 hours. The reaction mixture was poured into ice water to filtrate a crystal precipitated. The crystal obtained was dissolved in tetrahydrofuran to filter off undissolved substances,and purified by silica gel column chromatography (eluent: chloroform) to give 6.0 g (yield 59.9%) of the title compound.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US06028079uspto-grants-2000_02