Diethyl Ether → Oct-5-en-7-yn-2-one

HRID 484563Notes

Reaction equation

HRID 484563 reaction equation
Br[CH2:2][CH:3]=[C:4](C)[C:5]#[CH:6].C(=O)([O-])[O-].[K+].[K+].CC(=O)[CH2:16][C:17](=[O:19])[CH3:18].CCOCC>C(O)C.O.CCCCCC>[CH3:16][C:17](=[O:19])[CH2:18][CH2:2][CH:3]=[CH:4][C:5]#[CH:6]

Participants

8

Reactant 4

HCID 3283Diethyl EtherHCID 11430Potassium CarbonateHCID 31261AcetylacetoneHCID 53693355HCID 53693355, compound

Product 1

HCID 53435894Oct-5-en-7-yn-2-oneYield 77.2%

Reagents, catalysts & solvents 3

HCID 702EthanolSolventHCID 962WaterSolventHCID 8058HexaneSolvent

Procedure

In accordance with a procedure suggested by L. Miginiac, et al., Org. Prep. Proced. Int., 10, 261 (1978), a mixture containing 2.81 g (17.7 mmoles) of 5-bromo-3-methyl-3-penten-1-yne (produced in accordance with Example I), 3.27 g (23.6 mmoles) of anhydrous potassium carbonate, and 2.00 mL (19.5 mmoles) of 2,4-pentanedione (purchased from Aldrich Chemical Co., Milwaukee, Wis.) in 12.0 mL of absolute ethanol was heated, protected from atmospheric moisture, at reflux for 19 hours. The cooled mixture was diluted with 60 mL of water to dissolve the inorganic solids and the product was isolated by extraction (3×60 mL) with 1:1 (v/v) ether:hexane. After subsequent washing of the combined organic extracts with 10% aqueous sodium chloride (3×80 mL), the organic layer was dried over anhydrous magnesium sulfate and filtered. Removal of the volatile organic solvents by evaporation at reduced pressure, followed by evaporative distillation, afforded 1.67 g (69% yield) of the named ketone: boiling point 82°-91° C. (bath temperature, 2.5 mm). The identity and purity of this known ketone were ascertained by IR and proton NMR analysis. An alternate synthesis of this ketone has been described by P. I. Zakharova, et al., Chem. Abstracts. 75, 109784h (1971).

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 19 hours
  3. dissolutionto dissolve the inorganic solids
  4. washAfter subsequent washing of the combined organic extracts with 10% aqueous sodium chloride (3×80 mL)
  5. dry with materialthe organic layer was dried over anhydrous magnesium sulfate
  6. filtrationfiltered
  7. customRemoval of the volatile organic solvents
  8. customby evaporation at reduced pressure
  9. distillationfollowed by evaporative distillation

Sources & evidence

ORD record
ord-a82298e51fb54338a00e1e2f0687440b
Source dataset
uspto-grants-1993_07
Patent number
US05231232

Reaction notes

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