Ethyl bromoacetate → Ethyl 3-acetyl-4-oxopentanoate

HRID 2292634Notes

Reaction equation

HRID 2292634 reaction equation
[CH3:1][C:2](=[O:7])[CH2:3][C:4](=[O:6])[CH3:5].Br[CH2:9][C:10]([O:12][CH2:13][CH3:14])=[O:11].C(=O)([O-])[O-].[K+].[K+]>CC(C)=O>[C:4]([CH:3]([C:2](=[O:7])[CH3:1])[CH2:9][C:10]([O:12][CH2:13][CH3:14])=[O:11])(=[O:6])[CH3:5]

Participants

5

Reactant 3

HCID 7748Ethyl bromoacetateHCID 11430Potassium CarbonateHCID 31261Acetylacetone

Product 1

HCID 87820Ethyl 3-acetyl-4-oxopentanoateYield 56.9%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A solution of 28.2 ml (0.275 moles) of 2,4-pentanedione and 27.7 ml (0.25 moles) of ethyl bromoacetate in 50 ml of acetone was stirred under nitrogen while 38.0 g (0.275 moles) of dry potassium carbonate, predried at 100° C. under vacuum for 18 hours, was added. The mixture was heated to reflux for 4.5 hours. After cooling, the mixture was separated by filtration and the solid was washed with two portions of 50 ml of acetone. The filtrate was concentrated to dryness, dissolved in methylene chloride, filtered through Fluorosil, concentrated under vacuum to dryness, leaving a residual oil which was distilled. The fraction distilling at 48°-52° C. at 0.05 mm pressure was collected and 26.5 g of ethyl 3-acetyl-4-oxopentanoate were obtained.

Workup

  1. additionwas added
  2. temperatureThe mixture was heated
  3. temperatureto reflux for 4.5 hours
  4. temperatureAfter cooling
  5. customthe mixture was separated by filtration
  6. washthe solid was washed with two portions of 50 ml of acetone
  7. concentrationThe filtrate was concentrated to dryness
  8. dissolutiondissolved in methylene chloride
  9. filtrationfiltered through Fluorosil
  10. concentrationconcentrated under vacuum to dryness
  11. customleaving a residual oil which
  12. distillationwas distilled
  13. distillationThe fraction distilling at 48°-52° C. at 0.05 mm pressure
  14. customwas collected

Sources & evidence

ORD record
ord-a1ed91f203a24f82a43cb3a7ec513663
Source dataset
uspto-grants-1997_11
Patent number
US05684024

Reaction notes

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