2-Methyl-3-butyn-2-ol → 1-Ethynyl-4-(1-methylethyl)benzene

HRID 1761381Notes

Reaction equation

HRID 1761381 reaction equation
[CH3:1][CH:2]([C:4]1[CH:9]=[CH:8][C:7](Br)=[CH:6][CH:5]=1)[CH3:3].[CH3:11][C:12](C)(O)C#C>C(N(CC)CC)C.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[Cu]I>[CH3:1][CH:2]([C:4]1[CH:9]=[CH:8][C:7]([C:11]#[CH:12])=[CH:6][CH:5]=1)[CH3:3]

Participants

6

Reactant 2

HCID 82582-Methyl-3-butyn-2-olHCID 114621-Bromo-4-isopropylbenzene

Product 1

HCID 6375011-Ethynyl-4-(1-methylethyl)benzeneYield 33.3%

Reagents, catalysts & solvents 3

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)CatalystHCID 178418476HCID 178418476, compoundCatalystHCID 8471TriethylamineSolvent

Procedure

A solution of 10 grams (0.050 mole) of 4-(1-methylethyl)bromobenzene and 8.4 grams (0.10 mole) of 1,1-dimethyl-2-propyn-1-ol in 75 mL of triethylamine was stirred, and 0.7 gram (0.001 mole) of bis(triphenylphosphine)palladium(II) chloride and 0.2 gram (0.001 mole) of copper (I) iodide were added. Upon completion of addition the reaction mixture was heated under reflux for four hours. The reaction mixture was cooled and concentrated under reduced pressure to a residue. The residue was dissolved in diethyl ether and was washed first with an aqueous 10% ammonium chloride solution, then with water. The organic layer was dried with magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure to a residual oil. The oil was dissolved in 100 mL of toluene, 4.0 grams of sodium hydroxide was added to the solution, and the mixture was heated under reflux for four hours. The mixture was allowed to cool to ambient temperature where it stood for 18 hours. After this time the mixture was concentrated under reduced pressure to a residual oil. The oil was subjected to column chromatography on silica gel. Elution was accomplished with 1-20% chloroform in hexane. The appropriate fractions were combined and concentrated under reduced pressure to yield 2.4 grams of 4-(1-methylethyl)phenylethyne as an oil. The nmr spectrum was consistent with the proposed structure.

Workup

  1. additionUpon completion of addition the reaction mixture
  2. temperaturewas heated
  3. temperatureunder reflux for four hours
  4. temperatureThe reaction mixture was cooled
  5. concentrationconcentrated under reduced pressure to a residue
  6. dissolutionThe residue was dissolved in diethyl ether
  7. washwas washed first with an aqueous 10% ammonium chloride solution
  8. dry with materialThe organic layer was dried with magnesium sulfate
  9. filtrationfiltered
  10. concentrationThe filtrate was concentrated under reduced pressure to a residual oil
  11. dissolutionThe oil was dissolved in 100 mL of toluene
  12. addition4.0 grams of sodium hydroxide was added to the solution
  13. temperaturethe mixture was heated
  14. temperatureunder reflux for four hours
  15. concentrationAfter this time the mixture was concentrated under reduced pressure to a residual oil
  16. washElution
  17. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-0c9f747183b049d8a7f4eb669493d9f0
Source dataset
uspto-grants-1989_05
Patent number
US04826829

Reaction notes

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