Ethylene → 2,4,4-trimethylcyclohex-2-en-1-one

HRID 893421Notes

Reaction equation

HRID 893421 reaction equation
[Cl-].[Al+3].[Cl-].[Cl-].[C:5](Cl)(=[O:8])[CH2:6][CH3:7].[CH2:10]=[CH2:11].[CH3:12][CH:13]([CH3:16])[CH:14]=O>C1(C)C=CC(S(O)(=O)=O)=CC=1.O.ClCCCl>[CH3:10][C:11]1[C:5](=[O:8])[CH2:6][CH2:7][C:13]([CH3:16])([CH3:14])[CH:12]=1

Participants

8

Reactant 4

HCID 6325EthyleneHCID 6561IsobutyraldehydeHCID 62324Propionyl chlorideHCID 6451240Aluminum(III) Chloride

Product 1

HCID 50869122,4,4-trimethylcyclohex-2-en-1-oneYield 72.4%

Reagents, catalysts & solvents 3

HCID 6101p-Toluenesulfonic acidCatalystHCID 111,2-DichloroethaneSolventHCID 962WaterSolvent2×

Conditions

Temperature
0 °C

Procedure

Aluminium chloride (60.6 g, 0.454 moles) Was added to 1,2-dichloroethane (200 ml) and the mixture cooled to about 0° C. Propanoyl chloride (40 g, 0.432 moles) was then added over a period of 20 minutes and the temperature of the reaction mixture allowed to rise to 20° C. to give a clear pale orange solution. This solution was stirred for 30 minutes and ethene (12 g, 0.432 moles) was then bubbled into the solution over a period of about 11/2 hours. The mixture was then quenched in a mixture of concentrated hydrochloric acid (65 ml) and ice (330 ml) and the organic phase separated and backwashed with water (2×50 ml). 2-Methylpropanal (22 g, 0.3 moles) and para-toluenesulphonic acid (1.65 g, 8.64 mmoles) were then added and the mixture refluxed with azeotropic water removal until no more water separated. The organic phase was then washed with 10% (w/v) sodium hydroxide (200 ml) and the solvent removed. Distillation gave 30 g 2,4,4-trimethylcyclohex-2-en-1-one, b.pt. 40° C. at 0.3 mm Hg. (Yield: 72%)

Workup

  1. customto rise to 20° C.
  2. customto give a clear pale orange solution
  3. customThe mixture was then quenched in a mixture of concentrated hydrochloric acid (65 ml) and ice (330 ml)
  4. customthe organic phase separated
  5. customseparated
  6. washThe organic phase was then washed with 10% (w/v) sodium hydroxide (200 ml)
  7. customthe solvent removed
  8. distillationDistillation

Sources & evidence

ORD record
ord-2169cb833c66491eb3eeeb1fc971cfcc
Source dataset
uspto-grants-1992_06
Patent number
US05124486

Reaction notes

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