Diethyl Malonate → 5-(2,5-Difluorophenyl)cyclohexane-1,3-dione

HRID 49204Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 49204
[O-:1][CH2:2][CH3:3].[Na+].C(OCC)(=O)CC(OCC)=O.[F:16][C:17]1[CH:22]=[CH:21][C:20]([F:23])=[CH:19][C:18]=1[CH:24]=[CH:25][C:26](=[O:28])[CH3:27]>C(O)C>[F:16][C:17]1[CH:22]=[CH:21][C:20]([F:23])=[CH:19][C:18]=1[CH:24]1[CH2:3][C:2](=[O:1])[CH2:27][C:26](=[O:28])[CH2:25]1

Komponenten

5

Edukt 3

HCID 7761Diethyl MalonateHCID 14817594-(2,5-Difluorophenyl)but-3-en-2-oneHCID 2723922Sodium ethoxide

Produkt 1

HCID 178239175-(2,5-Difluorophenyl)cyclohexane-1,3-dione

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 702EthanolLösungsmittel

Versuchsvorschrift

A 20% solution of sodium ethoxide in ethanol (27.7 g) was combined at room temperature with diethyl malonate (13.0 g) and then with 4-(2,5-difluorophenyl)-3-buten-2-one (13.8 g) in portions. The reaction mixture was stirred at room temperature for 30 minutes and then heated with stirring for 2 hours. After allowing to stand to cool, the solvent was distilled off, and the residue was combined with water, and the aqueous layer was washed with ethyl acetate and concentrated. 2N Sodium hydroxide (42 ml) was added and the mixture was heated under reflux for 2 hours. After allowing to stand to cool, 2.5 M sulfuric acid (42 ml) was added over a period of 10 minutes, and then the mixture was heated under reflux for 3 hours. After allowing to stand to cool, the precipitated crystal was recovered by a filtration and washed successively with water and isopropyl ether to obtain 5-(2,5-difluorophenyl)cyclohexane-1,3-dione (11.6 g) as a colorless crystal.

Aufarbeitung

  1. temperatureheated
  2. stirringwith stirring for 2 hours
  3. temperatureto cool
  4. distillationthe solvent was distilled off
  5. washthe aqueous layer was washed with ethyl acetate
  6. concentrationconcentrated
  7. addition2N Sodium hydroxide (42 ml) was added
  8. temperaturethe mixture was heated
  9. temperatureunder reflux for 2 hours
  10. temperatureto cool
  11. addition2.5 M sulfuric acid (42 ml) was added over a period of 10 minutes
  12. temperaturethe mixture was heated
  13. temperatureunder reflux for 3 hours
  14. temperatureto cool
  15. filtrationthe precipitated crystal was recovered by a filtration
  16. washwashed successively with water and isopropyl ether

Quellen und Nachweise

ORD-Eintrag
ord-e07e38f0d5e64a5f89e32ee15caa85ee
Quelldatensatz
uspto-grants-2004_03
Patentnummer
US06706732B1

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