Hydrochloric Acid → 2,3,4-Trifluoro-5-pivaloylaminophenol

HRID 1736248Notes

Reaction equation

HRID 1736248 reaction equation
[NH2:1][C:2]1[C:3]([F:16])=[C:4]([F:15])[C:5]([F:14])=[C:6]([O:8]C(OCC)=O)[CH:7]=1.[C:17](Cl)(=[O:22])[C:18]([CH3:21])([CH3:20])[CH3:19].Cl.C(=O)([O-])[O-].[K+].[K+]>N1C=CC=CC=1.O>[F:14][C:5]1[C:4]([F:15])=[C:3]([F:16])[C:2]([NH:1][C:17](=[O:22])[C:18]([CH3:21])([CH3:20])[CH3:19])=[CH:7][C:6]=1[OH:8]

Participants

7

Reactant 4

HCID 313Hydrochloric Acid2×HCID 11430Potassium CarbonateHCID 62493Pivaloyl chlorideHCID 867496575-amino-O-ethoxycarbonyl-2,3,4-trifluorophenol

Product 1

HCID 194349822,3,4-Trifluoro-5-pivaloylaminophenolYield 90%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 1049PyridineSolvent

Procedure

1.27 g (5.40 mmol) of the above 5-amino-O-ethoxycarbonyl-2,3,4-trifluorophenol was dissolved in 5 mL of pyridine, 0.80 mL (6.5 mmol) of pivaloyl chloride was added under ice-cooling and the mixture was stirred at the same temperature for 15 minutes. 1N hydrochloric acid was added to the reaction solution and the mixture was extracted once with ethyl acetate. The organic layer was washed once with water and once with an aqueous saturated solution of sodium chloride, dried over anhydrous sodium sulfate and the solvent was distilled off under reduced pressure. The residue was dissolved in 25 mL of methanol, 1.40 g (10.1 mmol) of potassium carbonate and 15 mL of water were added and the mixture was stirred at room temperature for 4 hours. The reaction solution was adjusted to pH 2 by addition of 2N hydrochloric acid thereto and the mixture was extracted once with ethyl acetate. The organic layer was washed once with water and once with an aqueous saturated solution of sodium chloride, and dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to give 1.20 g of 2,3,4-trifluoro-5-pivaloylaminophenol (two stage yield: 90%).

Workup

  1. temperaturecooling
  2. extractionthe mixture was extracted once with ethyl acetate
  3. washThe organic layer was washed once with water and once with an aqueous saturated solution of sodium chloride
  4. dry with materialdried over anhydrous sodium sulfate
  5. distillationthe solvent was distilled off under reduced pressure
  6. dissolutionThe residue was dissolved in 25 mL of methanol
  7. stirringthe mixture was stirred at room temperature for 4 hours
  8. extractionthe mixture was extracted once with ethyl acetate
  9. washThe organic layer was washed once with water and once with an aqueous saturated solution of sodium chloride
  10. dry with materialdried over anhydrous sodium sulfate
  11. distillationthe solvent was distilled off under reduced pressure

Sources & evidence

ORD record
ord-91e3fccaefa547d9ad549c0637cfe2c1
Source dataset
uspto-grants-1996_07
Patent number
US05539112

Reaction notes

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