Acetic Acid → 3-[2-Chloro-4-(trifluoromethyl)phenoxy]benzoic acid

HRID 2285599

Reaktionsgleichung

Reaktionsgleichung von HRID 2285599
[Cl:1][C:2]1[CH:15]=[C:14]([C:16]([F:19])([F:18])[F:17])[CH:13]=[CH:12][C:3]=1[O:4][C:5]1[CH:6]=C(C)[CH:8]=[CH:9][CH:10]=1.Br.O=O.OO.[C:25]([OH:28])(=[O:27])[CH3:26]>O.O.O.O.C([O-])(=O)C.[Co+2].C([O-])(=O)C>[Cl:1][C:2]1[CH:15]=[C:14]([C:16]([F:17])([F:19])[F:18])[CH:13]=[CH:12][C:3]=1[O:4][C:5]1[CH:6]=[C:26]([CH:8]=[CH:9][CH:10]=1)[C:25]([OH:28])=[O:27]

Komponenten

7

Reaktionsbedingungen

Temperatur
90 °C

Versuchsvorschrift

Into a three liter flask is added 1.3 liters of acetic acid, 614 g. (1.90 mole) of 88.8% pure 3-(2-chloro-4-trifluoromethylphenoxy)toluene, and 32.0 g. (0.128 mole) of cobalt acetate tetrahydrate. To this stirred pink solution is added 20.0 ml (0.173 mole) of 47% aqueous hydrogen bromide whereupon the solution turns blue. The solution is then heated to 90° C. and a flow of oxygen (100%, 2.19×10-2 mole/min) is initiated. Hydrogen peroxide 10.0 ml (30%, 0.088 mole) is then added via a syringe to the solution and the exotherm raises the reaction temperature to 98° C. within 5 minutes. The reaction is monitored by thin layer chromatography and is complete within 4 hours. Isolation of the oxidation product 3-(2-chloro-4-trifluoromethylphenoxy)benzoic acid from the reaction mixture is accomplished by distillation of the acetic acid solvent, neutralization with aqueous sodium hydroxide to a pH of 11, filtration to remove the insoluble cobalt hydroxides and acidification of the filtrate with sulfuric acid to precipitate the product, which is filtered and dried to give 680.3 g of 85.1% 3-(2-chloro-4-trifluoromethylphenoxy)benzoic acid. This represents of 96.1% yield of this product based on the 3-(2-chloro-4-trifluoromethylphenoxy)toluene starting material.

Aufarbeitung

  1. temperaturethe exotherm raises the reaction temperature to 98° C. within 5 minutes
  2. distillationIsolation of the oxidation product 3-(2-chloro-4-trifluoromethylphenoxy)benzoic acid from the reaction mixture is accomplished by distillation of the acetic acid solvent, neutralization with aqueous sodium hydroxide to a pH of 11, filtration
  3. customto remove the insoluble cobalt hydroxides and acidification of the filtrate with sulfuric acid
  4. customto precipitate the product, which
  5. filtrationis filtered
  6. customdried

Quellen und Nachweise

ORD-Eintrag
ord-cbb67587f66a420393c0bd29383bec37
Quelldatensatz
uspto-grants-1982_04
Patentnummer
US04323692

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