Trichloroacetyl isocyanate → 2-Methoxyimino-2-(3-carbamoyloxyphenyl)acetic acid

HRID 2412708Notes

Reaction equation

HRID 2412708 reaction equation
ClC(Cl)(Cl)C([N:5]=[C:6]=[O:7])=O.[CH3:10][O:11][N:12]=[C:13]([C:17]1[CH:22]=[CH:21][CH:20]=[C:19]([OH:23])[CH:18]=1)[C:14]([OH:16])=[O:15]>O1CCOCC1>[CH3:10][O:11][N:12]=[C:13]([C:17]1[CH:22]=[CH:21][CH:20]=[C:19]([O:23][C:6](=[O:7])[NH2:5])[CH:18]=1)[C:14]([OH:16])=[O:15]

Participants

4

Reactant 2

HCID 76400Trichloroacetyl isocyanateHCID 543905512-Methoxyimino-2-(3-hydroxyphenyl)acetic acid

Product 1

HCID 543451492-Methoxyimino-2-(3-carbamoyloxyphenyl)acetic acid

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

Trichloroacetyl isocyanate (70 ml) was dropwise added over 6 minutes at ambient temperature to a solution of 2-methoxyimino-2-(3-hydroxyphenyl)acetic acid (syn isomer) (40 g) in dry dioxane (200 ml), and the resulting mixture was stirred for 5 hours at ambient temperature. Dioxane was distilled off and to the residue were added ethyl acetate (200 ml) and by small portions water (200 ml) under ice-cooling. The mixture containing trichloroacetylcarbamoyl 2-methoxyimino-2-(3-trichloroacetylcarbamoyloxyphenyl)acetate was stirred for 5 hours at ambient temperature keeping the pH value of the mixture at 6.0 to 6.4 by adding an aqueous solution of sodium bicarbonate. The resulting mixture was wahsed twice with ethyl acetate. The aqueous layer was adjusted to pH2 with a 10% hydrochloric acid and extracted three times with ethyl acetate. The combined ethyl acetate extracts were washed twice with an aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off and precipitating crystals were collected by filtration to give colorless crystals of 2-methoxyimino-2-(3-carbamoyloxyphenyl)acetic acid (syn isomer) (15 g), mp 163° C. (dec.). The same compound (5.4 g) was obtained from the mother liquor.

Workup

  1. distillationDioxane was distilled off and to the residue
  2. additionwere added ethyl acetate (200 ml)
  3. temperatureby small portions water (200 ml) under ice-cooling
  4. additionThe mixture containing trichloroacetylcarbamoyl 2-methoxyimino-2-(3-trichloroacetylcarbamoyloxyphenyl)acetate
  5. stirringwas stirred for 5 hours at ambient temperature
  6. additionby adding an aqueous solution of sodium bicarbonate
  7. extractionextracted three times with ethyl acetate
  8. washThe combined ethyl acetate extracts were washed twice with an aqueous solution of sodium chloride
  9. dry with materialdried over magnesium sulfate
  10. distillationThe solvent was distilled off
  11. customprecipitating crystals
  12. filtrationwere collected by filtration

Sources & evidence

ORD record
ord-34339335564f48cc9721fa426845f2cb
Source dataset
uspto-grants-1985_01
Patent number
US04493833

Reaction notes

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