Hydrochloric Acid → 3-(4-Chlorophenyl)-1,2-oxazole-4-carboxylic acid

HRID 1911651Notes

Reaction equation

HRID 1911651 reaction equation
C([O:3][C:4]([C:6]1[C:7]([C:11]2[CH:16]=[CH:15][C:14]([Cl:17])=[CH:13][CH:12]=2)=[N:8][O:9][CH:10]=1)=[O:5])C.[OH-].[Na+].Cl>C(O)C>[Cl: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 871629Ethyl 3-(4-chlorophenyl)-1,2-oxazole-4-carboxylate

Product 1

HCID 289494543-(4-Chlorophenyl)-1,2-oxazole-4-carboxylic acidYield 100.1%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a solution of 3-(4-chloro-phenyl)-isoxazole-4-carboxylic acid ethyl ester (57.0 g, 226.5 mmol) in ethanol (234 mL) was added aqueous sodium hydroxide (2 N, 175 mL, 351 mmol) and the resulting mixture stirred overnight at room temperature. The mixture was then acidified with HCl solution (4 N, 92.6 mL) to pH 2-3. The precipitate was then filtered off and dissolved in THF (762 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 (50.7 g, 92%) which was obtained as a light yellow solid. MS: m/e=222.3 [M−H]−.

Workup

  1. filtrationThe precipitate was then filtered off
  2. dissolutiondissolved in THF (762 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-d682c034d37b44d6adbdea2801ffae4a
Source dataset
uspto-grants-2013_12
Patent number
US08604062B2

Reaction notes

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