p-Toluenesulfonic acid → Ethyl 3-oxo-(2,3,4,5-tetrafluorophenyl)propanoate

HRID 1710179Notes

Reaction equation

HRID 1710179 reaction equation
C1(C)C=CC(S(O)(=O)=O)=CC=1.[F:12][C:13]1[C:31]([F:32])=[C:30]([F:33])[C:29]([F:34])=[CH:28][C:14]=1[C:15]([CH:17](C(OCC)=O)[C:18]([O:20][CH2:21][CH3:22])=[O:19])=[O:16]>O>[F:12][C:13]1[C:31]([F:32])=[C:30]([F:33])[C:29]([F:34])=[CH:28][C:14]=1[C:15]([CH2:17][C:18]([O:20][CH2:21][CH3:22])=[O:19])=[O:16]

Participants

4

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 135649731,3-Diethyl 2-(2,3,4,5-tetrafluorobenzoyl)propanedioate

Product 1

HCID 600916Ethyl 3-oxo-(2,3,4,5-tetrafluorophenyl)propanoateYield 71.6%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

0.3 g of p-toluenesulphonic acid is added to an emulsion of 284.8 g of crude diethyl 2,3,4,5-tetrafluoro- benzoyl-malonate (3) in 300 ml of water. The mixture is heated to the boil for 5 hours, while stirring thoroughly, the cold emulsion is extracted several times with methylene chloride, the combined CH2Cl2 solutions are washed once with saturated NaCl solution and dried with Na2SO4, and the solvent is distilled off in vacuo. Fractionation of the residue in a fine vacuum gives 160.2 g of ethyl 2,3,4,5-tetrafluorobenzoyl-acetate (4) of boiling point 100°-110° C./0.09-0.1 mbar. Melting point 47°-49° C.

Workup

  1. temperatureThe mixture is heated to the boil for 5 hours
  2. extractionthe cold emulsion is extracted several times with methylene chloride
  3. washthe combined CH2Cl2 solutions are washed once with saturated NaCl solution
  4. dry with materialdried with Na2SO4
  5. distillationthe solvent is distilled off in vacuo

Sources & evidence

ORD record
ord-538e36b5cd8e46db9c6188dae3646415
Source dataset
uspto-grants-1990_08
Patent number
US04952695

Reaction notes

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