Phosphoric Acid → 1,1-Dimethylprop-2-ynyl acetate

HRID 616951Notes

Reaction equation

HRID 616951 reaction equation
[CH3:1][C:2]([CH3:6])([C:4]#[CH:5])[OH:3].P(=O)(O)(O)O.[C:12](OC(=O)C)(=[O:14])[CH3:13]>C(OC(=O)C)(=O)C.CO>[C:12]([O:3][C:2]([CH3:6])([CH3:1])[C:4]#[CH:5])(=[O:14])[CH3:13]

Participants

6

Reactant 3

HCID 1004Phosphoric AcidHCID 7918Acetic AnhydrideHCID 82582-Methyl-3-butyn-2-ol

Product 1

HCID 741441,1-Dimethylprop-2-ynyl acetate

Reagents, catalysts & solvents 2

HCID 7918Acetic AnhydrideCatalystHCID 887MethanolSolvent

Procedure

112 g (one mole) of freshly distilled dimethylethynyl carbinol is treated with 1.2 moles of acetic anhydride containing 10 drops of 85% phosphoric acid. The acetic anhydride is added to the carbinol dropwise with shaking while maintaining the temperature under 40°. The mixture is allowed to stand overnight, washed with two 75 ml portions of cold water, and the water washings are extracted with ether. The ether extract is added to the main portion of ester and the combined ethereal solution is washed with 10% sodium carbonate solution until the washings remain basic to litmus. The solution is washed with two 75 ml portions of ice-water, dried over calcium chloride, and distilled to give the title compound.

Workup

  1. temperaturewhile maintaining the temperature under 40°
  2. washwashed with two 75 ml portions of cold water
  3. extractionthe water washings are extracted with ether
  4. extractionThe ether extract
  5. additionis added to the main portion of ester
  6. washthe combined ethereal solution is washed with 10% sodium carbonate solution until the washings
  7. washThe solution is washed with two 75 ml portions of ice-water
  8. dry with materialdried over calcium chloride
  9. distillationdistilled

Sources & evidence

ORD record
ord-a67e2b74261c48b59d9ffc6b9c42d37a
Source dataset
uspto-grants-1978_02
Patent number
US04076818

Reaction notes

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