Phenethyl bromide → 5-Phenylpentan-2-one

HRID 1861618Notes

Reaction equation

HRID 1861618 reaction equation
[Na].C(OCC)(=O)[CH2:3][C:4]([CH3:6])=[O:5].[C:11]1([CH2:17][CH2:18]Br)[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1>C(O)C>[C:11]1([CH2:17][CH2:18][CH2:3][C:4](=[O:5])[CH3:6])[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1

Participants

5

Reactant 3

HCID 7666Phenethyl bromideHCID 8868Ethyl AcetoacetateHCID 5360545Sodium2×

Product 1

HCID 167015-Phenylpentan-2-one

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

According to reference F. C. Montgomery, W. H. Saunders, Jr. J. Org. Chem. 1976, 41, 2368-72, 7.6 g of sodium are added to 200 ml of absolute ethanol. Once the sodium has dissolved, 43 g (0.33 mol) of ethyl acetoacetate are added dropwise within an hour, the mixture refluxed for 1 hour, 65 g of 2-phenylethyl bromide are slowly added dropwise and the mixture is refluxed again (21 hours). After cooling and filtration, the mixture is distilled. The product is first heated for 5 h to 90° C. with 350 ml of 5% sodium hydroxide, then stirred for 5 hours at the same temperature with 150 ml of 50% sulfuric acid. After cooling, the product is left to stand for 48 hours, extracted with diethyl ether, the combined extracts are dried over sodium sulfate and 3a is finally obtained in good yield by distillation (b.p.: 132-134° C., 2.3 103 Pa (17 Torr)).

Workup

  1. temperaturethe mixture refluxed for 1 hour
  2. temperaturethe mixture is refluxed again (21 hours)
  3. temperatureAfter cooling
  4. filtrationfiltration
  5. distillationthe mixture is distilled
  6. temperatureThe product is first heated for 5 h to 90° C. with 350 ml of 5% sodium hydroxide
  7. temperatureAfter cooling
  8. waitthe product is left
  9. waitto stand for 48 hours
  10. extractionextracted with diethyl ether
  11. dry with materialthe combined extracts are dried over sodium sulfate and 3a
  12. customis finally obtained
  13. customin good yield by distillation (b.p.: 132-134° C., 2.3 103 Pa (17 Torr))

Sources & evidence

ORD record
ord-5d5c1bb3cb6b4e3da9a48f3cc4bc76ca
Source dataset
uspto-grants-2003_03
Patent number
US06534489B1

Reaction notes

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