Hydrochloric Acid → 3-(4-Fluoro-phenyl)-isoxazole-4-carboxylic acid

HRID 1897326Notes

Reaction equation

HRID 1897326 reaction equation
C([O:3][C:4]([C:6]1[C:7]([C:11]2[CH:16]=[CH:15][C:14]([F:17])=[CH:13][CH:12]=2)=[N:8][O:9][CH:10]=1)=[O:5])C.[OH-].[Na+].Cl>C(O)C>[F:17][C:14]1[CH:13]=[CH:12][C:11]([C:7]2[C:6]([C:4]([OH:5])=[O:3])=[CH:10][O:9][N:8]=2)=[CH:16][CH:15]=1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 743179Ethyl 3-(4-fluorophenyl)-1,2-oxazole-4-carboxylate

Product 1

HCID 234478853-(4-Fluoro-phenyl)-isoxazole-4-carboxylic acidYield 94.7%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a solution of 3-(4-fluoro-phenyl)-isoxazole-4-carboxylic acid ethyl ester (849 g, 208 mmol) in ethanol (215 mL) was added aqueous sodium hydroxide (2 N, 161 mL, 323 mmol) and the resulting mixture stirred overnight at room temperature. The mixture was then acidified with HCl solution (4 N, 85 mL) to pH 2-3. The precipitate was then filtered off and dissolved in THF (700 mL) and then washed with saturated sodium chloride solution. The aqueous phase was then extracted with ethyl acetate and THF (1:1, 300 mL) and the combined organic phases dried over sodium sulfate and evaporated to afford the title compound (40.8 g, 94%) which was obtained as an orange solid. MS: m/e=206.1 [M−H]−.

Workup

  1. filtrationThe precipitate was then filtered off
  2. dissolutiondissolved in THF (700 mL)
  3. washwashed with saturated sodium chloride solution
  4. extractionThe aqueous phase was then extracted with ethyl acetate and THF (1:1, 300 mL)
  5. dry with materialthe combined organic phases dried over sodium sulfate
  6. customevaporated

Sources & evidence

ORD record
ord-4b1ba64ba34e4095a2be8f067b98872e
Source dataset
uspto-grants-2013_08
Patent number
US08518974B2

Reaction notes

Loading…