Ethyl benzoylacetate → HCID 20262554, compound
Reaction equation
[C:1]([CH2:9][C:10]([O:12]CC)=[O:11])(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[C:15](=[O:18])(O)[O-].[Na+]>C(O)C>[C:2]1([C:1]2[O:8][C:1]([C:2]3[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=3)=[CH:9][C:15](=[O:18])[C:9]=2[C:10]([OH:12])=[O:11])[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
A 250 ml round-bottom flask is equipped with a mechanical stirrer, thermometer, and a distillation head and condenser set up to remove distillate. The flask is charged with 100 g (0.52 moles) ethyl benzoylacetate and 0.075 g sodium bicarbonate. The flask and its contents are heated by means of an oil bath over a period of about 5 hours at temperature from ambient to a maximum of 200° C. while the ethanol formed is continuously removed. Unreacted ethyl benzoylacetate is removed by vaccum distillation. The residue consisting of crude 3-benzoyl-6-phenyl-2H-pyran-2,4-(3H)-dione is then heated at 80°-85° C. with 500 g of 85% sulfuric acid for 4 hours. This mixture is poured into 1 liter of ice-water and the water extracted three times with 150 ml portions of chloroform. The combined chloroform extracts are stripped of volatiles on a rotary evaporator and the residue of 2,6-diphenyl-4-oxopyran-3-carboxylic acid isolated by fractional crystallization. A toluene solution of this pyrone is then treated with an equal molar quantity of 4-amino-2,2,6,6-tetramethylpiperidine and refluxed with removal of water by means of a Dean-Stark trap. When water has ceased to separate, the toluene is removed on a rotary evaporator and the residue cooled and treated with hexane to promote crystallization of the crude product. The product is further purified by fractional crystallization.
Workup
- customA 250 ml round-bottom flask is equipped with a mechanical stirrer
- customto remove distillate
- customformed
- customis continuously removed
- customUnreacted ethyl benzoylacetate is removed by vaccum distillation
- temperatureis then heated at 80°-85° C. with 500 g of 85% sulfuric acid for 4 hours
- additionThis mixture is poured into 1 liter of ice-water
- extractionthe water extracted three times with 150 ml portions of chloroform
- customThe combined chloroform extracts are stripped of volatiles on a rotary evaporator
Sources & evidence
- ORD record
- ord-e67a7a81d14b48eebbeecc376de43217
- Source dataset
- uspto-grants-1985_10
- Patent number
- US04548973
Reaction notes
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