Ethyl bromoacetate → ethyl 2-(4-oxo-4H-pyran-3-yloxy)acetate

HRID 2285849Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 2285849
[OH:1][C:2]1[C:7](=[O:8])[CH:6]=[CH:5][O:4][CH:3]=1.Br[CH2:10][C:11]([O:13][CH2:14][CH3:15])=[O:12].C(=O)([O-])[O-].[K+].[K+]>C(O)C>[O:8]=[C:7]1[CH:6]=[CH:5][O:4][CH:3]=[C:2]1[O:1][CH2:10][C:11]([O:13][CH2:14][CH3:15])=[O:12]

Komponenten

5

Edukt 3

HCID 7748Ethyl bromoacetateHCID 11430Potassium CarbonateHCID 681293-Hydroxy-4H-pyran-4-one

Produkt 1

HCID 20544471ethyl 2-(4-oxo-4H-pyran-3-yloxy)acetate

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 702EthanolLösungsmittel

Versuchsvorschrift

A mixture of 3-hydroxy-4H-pyran-4-one (1.12 g), ethyl 2-bromoacetate (1.7 g) and potassium carbonate (1.4 g) in ethanol (30 ml) was stirred at 67° to 70° C. for 75 minutes. The reaction mixture was allowed to stand at room temperature. An insoluble substance was filtered off, and the filtrate was adjusted to pH 4 to 5 with conc. hydrochloric acid and the ethanol was removed. To the residue was added ethyl acetate, and the resultant mixture was washed with an aqueous solution saturated with sodium chloride and dried over magnesium sulfate. After removal of the solvent, the residue was chromatographed on silica gel (15 g) with an eluent (ethyl acetate:benzene=1:5) to give crystals of ethyl 2-(4-oxo-4H-pyran-3-yloxy)acetate, mp 58° to 60° C.

Aufarbeitung

  1. customto stand at room temperature
  2. filtrationAn insoluble substance was filtered off
  3. customthe ethanol was removed
  4. additionTo the residue was added ethyl acetate
  5. washthe resultant mixture was washed with an aqueous solution saturated with sodium chloride
  6. dry with materialdried over magnesium sulfate
  7. customAfter removal of the solvent
  8. customthe residue was chromatographed on silica gel (15 g) with an eluent (ethyl acetate:benzene=1:5)

Quellen und Nachweise

ORD-Eintrag
ord-db02173d8a434830ab89b241b1d89085
Quelldatensatz
uspto-grants-1982_04
Patentnummer
US04324892

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