p-Toluenesulfonic acid → Ethyl 2,4-dichloro-5-fluorobenzoylacetate

HRID 637942Notes

Reaction equation

HRID 637942 reaction equation
C1(C)C=CC(S(O)(=O)=O)=CC=1.[Cl:12][C:13]1[CH:31]=[C:30]([Cl:32])[C:29]([F:33])=[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>[Cl:12][C:13]1[CH:31]=[C:30]([Cl:32])[C:29]([F:33])=[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 13326819Diethyl 2-(2,4-dichloro-5-fluorobenzoyl)malonate

Product 1

HCID 2774350Ethyl 2,4-dichloro-5-fluorobenzoylacetateYield 78.6%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

0.15 g of p-toluenesulphonic acid is added to an emulsion of 34.9 g of crude diethyl 2,4-dichloro-5-fluoro-benzoylmalonate (3) in 50 ml of water. The mixture is heated at the boiling point for 3 hours, while stirring thoroughly, the cooled 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 vacuo gives 21.8 g of ethyl 2,4-dichloro-5-fluoro-benzoylacetate (4) of boiling point 127° to 142° C./0.09 mbar.

Workup

  1. temperatureThe mixture is heated at the boiling point for 3 hours
  2. extractionthe cooled 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-61e782fae11f420e82560278c2f4c78f
Source dataset
uspto-grants-1985_12
Patent number
US04559342

Reaction notes

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