Phosphorus oxychloride → 4-Chloro-2-ethoxy-6,7,8-trifluoroquinoline

HRID 344890Notes

Reaction equation

HRID 344890 reaction equation
[CH2:1]([O:3][C:4]1[CH:13]=[C:12](O)[C:11]2[C:6](=[C:7]([F:17])[C:8]([F:16])=[C:9]([F:15])[CH:10]=2)[N:5]=1)[CH3:2].P(Cl)(Cl)([Cl:20])=O>O>[Cl:20][C:12]1[C:11]2[C:6](=[C:7]([F:17])[C:8]([F:16])=[C:9]([F:15])[CH:10]=2)[N:5]=[C:4]([O:3][CH2:1][CH3:2])[CH:13]=1

Participants

4

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178467010HCID 178467010, compound

Product 1

HCID 542558274-Chloro-2-ethoxy-6,7,8-trifluoroquinoline

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
100 °C

Procedure

A suspension of 2-ethoxy-6,7,8-trifluoro-4-hydroxyquinoline (69.5 g) is phosphoryl chloride (430 cc) is heated with stirring to a temperature in the region of 100° C. for 30 minutes. The solution obtained is concentrated under reduced pressure (20 kPa) at approximately 60° C. to a volume of 100 cc. The residue is taken up with ethyl acetate (750 cc); the solution obtained is poured with stirring in the course of 10 minutes into a mixture of water (400 cc) and ice (200 g), and left stirring under these conditions for 30 minutes. After separation of the organic extract, the aqueous phase is again extracted with ethyl acetate (2×250 cc). The combined organic extracts are washed with water (3×250 cc), dried over magnesium sulphate and concentrated under reduced pressure (20 kPa) at approximately 40° C. The oily residue obtained is taken up with petroleum ether (40-60) (370 cc). After filtration through diatomaceous silica, the filtrate is concentrated to dryness under reduced pressure (20 kPa) at approximately 30° C. 4-Chloro-2-ethoxy-6,7,8-trifluoroquinoline (70.7 g) is obtained in the form of a beige solid, m.p. 45° C., which is used without further purification for the subsequent steps.

Workup

  1. temperatureis heated
  2. customThe solution obtained
  3. concentrationis concentrated under reduced pressure (20 kPa) at approximately 60° C. to a volume of 100 cc
  4. customthe solution obtained
  5. additionis poured
  6. waitleft
  7. stirringstirring under these conditions for 30 minutes
  8. customAfter separation of the organic extract
  9. extractionthe aqueous phase is again extracted with ethyl acetate (2×250 cc)
  10. washThe combined organic extracts are washed with water (3×250 cc)
  11. dry with materialdried over magnesium sulphate
  12. concentrationconcentrated under reduced pressure (20 kPa) at approximately 40° C
  13. customThe oily residue obtained
  14. filtrationAfter filtration through diatomaceous silica
  15. concentrationthe filtrate is concentrated to dryness under reduced pressure (20 kPa) at approximately 30° C

Sources & evidence

ORD record
ord-9b83a1942e354bd6aa72343be9adb75f
Source dataset
uspto-grants-1991_10
Patent number
US05053509

Reaction notes

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