Ethyl Acetoacetate → Ethyl 2-acetyl-3-methyl-4-oxopentanoate

HRID 1764569Notes

Reaction equation

HRID 1764569 reaction equation
[Na].[C:2]([O:8][CH2:9][CH3:10])(=[O:7])[CH2:3][C:4]([CH3:6])=[O:5].[O-]CC.[Na+].Br[CH:16]([CH3:20])[C:17](=[O:19])[CH3:18]>C(O)C>[CH2:9]([O:8][C:2]([CH:3]([CH:16]([CH3:20])[C:17](=[O:19])[CH3:18])[C:4](=[O:5])[CH3:6])=[O:7])[CH3:10]

Participants

6

Reactant 4

HCID 8868Ethyl AcetoacetateHCID 131422-Butanone, 3-bromo-HCID 2723922Sodium ethoxideHCID 5360545Sodium

Product 1

HCID 14689360Ethyl 2-acetyl-3-methyl-4-oxopentanoate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

7.3 G.; 0.317 mol of sodium was dissolved in 125 ml. of absolute ethanol. 87.0 G. (0.669 mol) of ethyl acetoacetate were added to the resulting solution of sodium ethoxide in the cold. The reaction was heated to reflux and 48.6 g. (0.322 mol) of freshly distilled 3-bromo-2-butanone were added dropwise with stirring over a period of 30 min. Refluxing was continued until the mixture tested neutral to pH paper (~1.5 hrs.). The precipitated sodium bromide was filtered off the cold solution and most of the ethanol was removed on an evaporator. The mixture was filtered again and distilled. The 3-ethoxycarbonyl-4-methylhexane-2,4-dione fraction which boiled at 131°-137° C./18 mm. was collected.

Workup

  1. temperatureThe reaction was heated
  2. temperatureto reflux
  3. temperatureRefluxing
  4. customtested neutral to pH paper (~1.5 hrs.)
  5. filtrationThe precipitated sodium bromide was filtered off the cold solution
  6. custommost of the ethanol was removed on an evaporator
  7. filtrationThe mixture was filtered again
  8. distillationdistilled
  9. customwas collected

Sources & evidence

ORD record
ord-89cce1ec130c4045a7c0f5b7e4a4f91d
Source dataset
uspto-grants-1978_09
Patent number
US04116975

Reaction notes

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