Acetone → Ethyl 3-(fur-2-yl)-3-oxopropanoate

HRID 1281735Notes

Reaction equation

HRID 1281735 reaction equation
[H-].[Na+].[C:3](=[O:10])([O:7][CH2:8][CH3:9])OCC.CC(C)=O.[O:15]1[CH:19]=[CH:18][CH:17]=[C:16]1[C:20](=[O:22])[CH3:21]>C1(C)C=CC=CC=1.O.C(O)(=O)C>[CH2:8]([O:7][C:3](=[O:10])[CH2:21][C:20]([C:16]1[O:15][CH:19]=[CH:18][CH:17]=1)=[O:22])[CH3:9]

Participants

8

Reactant 4

HCID 180AcetoneHCID 7766Diethyl CarbonateHCID 145052-AcetylfuranHCID 24758Sodium hydride

Product 1

HCID 2759240Ethyl 3-(fur-2-yl)-3-oxopropanoate

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolventHCID 962WaterSolventHCID 1140TolueneSolvent2×

Procedure

To a vigorously stirred suspension of NaH (60% dispersion in mineral oil, 2.28 g, 56.6 mmol, 2.9 equiv.) and diethyl carbonate (4.7 mL, 38.83 mmol, 1.99 equiv.) in dry toluene (30 mL) was added drop wise (over a period of 1 h) a solution of the methyl ketone, 1-furan-2-yl-ethanone, (2.14 g., 19.51 mmol) in toluene (5 mL) under reflux. After addition, the mixture was stirred at reflux for 0.5 h. The mixture was cooled to RT and was acidified with glacial acetic acid. After adding cold water, the mixture was extracted 3 times with ethyl acetate. Combined organic extract was washed with water and brine. After drying over MgSO4, solvent was evaporated to furnish the crude β-ketoester, 3-furan-2-yl-3-oxo-propionic acid ethyl ester. To the crude product was added absolute ethanol (10 mL) and hydrazine hydrate (1 mL). The mixture was kept under reflux for 3 h. Solvent was evaporated in vacuo. The crude mass was purified by flash chromatography (EtOAc). The solid obtained was stirred in EtOAc for 15 min., filtered and dried to furnish the pyrazolone (VIb) (1.23 g, 42%). 1H-NMR (DMSO-d6) δ 12.1 (br s, 1H), 9.5 (br s, 1H), 7.64 (s, 1H), 6.63 (s, 1H), 6.51 (s, 1H), 5.64 (s, 1H). (M+H).

Workup

  1. temperatureunder reflux
  2. additionAfter addition
  3. temperatureat reflux for 0.5 h
  4. extractionthe mixture was extracted 3 times with ethyl acetate
  5. extractionCombined organic extract
  6. washwas washed with water and brine
  7. dry with materialAfter drying over MgSO4, solvent
  8. customwas evaporated

Sources & evidence

ORD record
ord-144934c69c5e4142813a1199c504fb1b
Source dataset
uspto-grants-2002_09
Patent number
US06455525B1

Reaction notes

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