Sulfuric Acid → 5-Isoxazoleacetic acid, 3,4-bis(4-methoxyphenyl)-, methyl ester

HRID 1608970Notes

Reaction equation

HRID 1608970 reaction equation
[OH:1][N:2]=[C:3]([C:19]1[CH:24]=[CH:23][C:22]([O:25][CH3:26])=[CH:21][CH:20]=1)[C:4]([C:11]1[CH:16]=[CH:15][C:14]([O:17][CH3:18])=[CH:13][CH:12]=1)=[CH:5][CH2:6][C:7]([O:9][CH3:10])=[O:8].S(=O)(=O)(O)O>C(O)(=O)C.C([O-])(=O)C.[Co+2].C([O-])(=O)C>[CH3:10][O:9][C:7]([CH2:6][C:5]1[O:1][N:2]=[C:3]([C:19]2[CH:20]=[CH:21][C:22]([O:25][CH3:26])=[CH:23][CH:24]=2)[C:4]=1[C:11]1[CH:16]=[CH:15][C:14]([O:17][CH3:18])=[CH:13][CH:12]=1)=[O:8]

Participants

5

Reactant 2

HCID 1118Sulfuric AcidHCID 85301016Methyl 5-hydroxyimino-4,5-bis(4-methoxyphenyl)-3-pentenoate

Product 1

HCID 109262505-Isoxazoleacetic acid, 3,4-bis(4-methoxyphenyl)-, methyl esterYield 90%

Reagents, catalysts & solvents 2

HCID 6277Cobalt diacetateCatalystHCID 176Acetic AcidSolvent

Procedure

Methyl 5-hydroxyimino-4,5-bis(4-methoxyphenyl)-3-pentenoate (3.7 g) in 40 ml of acetic acid was stirred at 60° C. for 24 hours while blowing air into the mixture in the presence of 0.4 g of cobalt acetate. After completion of the reaction, 3N sulfuric acid was added and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with saturated aqueous potassium carbonate solution and saturated aqueous sodium chloride solution in that order, and dried over anhydrous magnesium sulfate. The organic layer was then concentrated under reduced pressure and the residue was separated and purified by silica gel column chromatography (developing solvent: ethyl acetate:n-hexane=1:2) to give 3.3 g (yield 90%) of 5-methoxycarbonylmethyl-3,4-bis(4-methoxyphenyl)isoxazole.

Workup

  1. additionwas added
  2. extractionthe resulting mixture was extracted with ethyl acetate
  3. washThe organic layer was washed with saturated aqueous potassium carbonate solution and saturated aqueous sodium chloride solution in that order
  4. dry with materialdried over anhydrous magnesium sulfate
  5. concentrationThe organic layer was then concentrated under reduced pressure
  6. customthe residue was separated
  7. custompurified by silica gel column chromatography (developing solvent: ethyl acetate:n-hexane=1:2)

Sources & evidence

ORD record
ord-d9c5822a43d445b188f81f0ee8d7a317
Source dataset
uspto-grants-1995_03
Patent number
US05399577

Reaction notes

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