Hydrochloric Acid → 2-propanoylcyclohexane-1,3-dione

HRID 2309604Notes

Reaction equation

HRID 2309604 reaction equation
[C:1]1(=[O:8])[CH2:6][CH2:5][CH2:4][C:3](=[O:7])[CH2:2]1.C(N(CC)CC)C.[C:16](Cl)(=[O:19])[CH2:17][CH3:18].CC(C)(O)C#N.Cl>C(Cl)Cl.O>[C:16]([CH:2]1[C:3](=[O:7])[CH2:4][CH2:5][CH2:6][C:1]1=[O:8])(=[O:19])[CH2:17][CH3:18]

Participants

8

Reactant 5

HCID 313Hydrochloric AcidHCID 6406Acetone CyanohydrinHCID 8471Triethylamine2×HCID 104341,3-CyclohexanedioneHCID 62324Propionyl chloride

Product 1

HCID 109209032-propanoylcyclohexane-1,3-dioneYield 84.3%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent2×

Procedure

To a mixture of 3.0 g (0.027 mole) of 1,3-cyclohexanedione and 3.8 ml (0.027 mole) of triethylamine in 15 ml methylene chloride, there was added dropwise 2.3 ml (0.027 mole) of propionyl chloride with stirring and cooling in a room temperature water bath. After continued stirring at ambient temperature for about 4 hours, an additional 7.5 ml (0.054 mole) of triethylamine and 0.25 ml (10 mole percent with respect to enol ester) of acetone cyanohydrin were added. The mixture was stirred at ambient temperature overnight, and was then diluted with water and acidified with 6N hydrochloric acid. The phases were separated, and the aqueous phase was extracted with methylene chloride. The combined organic phases were dried over anhydrous sodium sulfate and concentrated under reduced pressure to give 4.68 g of crude product as a mixture of solid and liquid. The crude product was dissolved in methylene chloride and was extracted with 2.5N sodium hydroxide solution followed by water. The combined aqueous phases were acidified with 6 N hydrochloric acid and extracted with methylene chloride. The organic extract was dried over anhydrous sodium sulfate and concentrated under reduced pressure to give 3.83 g of oily product (84% of theoretical). Structure of the product was confirmed by infrared, nuclear magnetic resonance and mass spectroscopy.

Workup

  1. stirringAfter continued stirring at ambient temperature for about 4 hours
  2. stirringThe mixture was stirred at ambient temperature overnight
  3. customThe phases were separated
  4. extractionthe aqueous phase was extracted with methylene chloride
  5. dry with materialThe combined organic phases were dried over anhydrous sodium sulfate
  6. concentrationconcentrated under reduced pressure
  7. customto give 4.68 g of crude product
  8. additionas a mixture of solid and liquid
  9. extractionwas extracted with 2.5N sodium hydroxide solution
  10. extractionextracted with methylene chloride
  11. extractionThe organic extract
  12. dry with materialwas dried over anhydrous sodium sulfate
  13. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-f2f173d1edc640028ab337297f93baab
Source dataset
uspto-grants-1987_09
Patent number
US04695673

Reaction notes

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