Ethanol → Ethyl 5-methylisoxazole-3-carboxylate

HRID 2050778Notes

Reaction equation

HRID 2050778 reaction equation
O=[C:2]([CH2:8][C:9](=[O:11])[CH3:10])[C:3]([O:5][CH2:6][CH3:7])=[O:4].S(O)(O)(=O)=O.[NH2:17]O.C(O)C.[OH-].[NH4+]>O.C1(C)C=CC=CC=1.C1(C)C=CC=CC=1>[CH3:10][C:9]1[O:11][N:17]=[C:2]([C:3]([O:5][CH2:6][CH3:7])=[O:4])[CH:8]=1

Participants

7

Reactant 4

HCID 702EthanolHCID 14923Ammonium HydroxideHCID 69208Ethyl 2,4-dioxovalerateHCID 159255Hydroxylamine, sulfate (1:1)

Product 1

HCID 76677Ethyl 5-methylisoxazole-3-carboxylateYield 118.3%

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 22272177Toluene waterSolvent

Conditions

Temperature
40 °C

Procedure

A mixture of 0.16 mole ethyl 2,4-dioxovalerate and 0.08 mole hydroxylamine sulfate, 50 ml ethanol and 70 ml toluene was stirred at 40° C. for four hours. The mixture was cooled to 15°-20° C., 1.8 g of concentrated ammonium hydroxide added and stirring continued at room temperature for 60 hours. The mixture was poured into water/toluene, the aqueous layer extracted with toluene, the organic layers combined, washed with brine and dried (Na2SO4). Evaporation of solvent in vacuo gave a yellow liquid which was distilled to afford 14.68 g of product, b.p. 120°-124° C. at 30 torr which crystallized upon standing.

Workup

  1. temperatureThe mixture was cooled to 15°-20° C.
  2. stirringstirring
  3. waitcontinued at room temperature for 60 hours
  4. extractionthe aqueous layer extracted with toluene
  5. washwashed with brine
  6. dry with materialdried (Na2SO4)
  7. customEvaporation of solvent in vacuo
  8. customgave a yellow liquid which
  9. distillationwas distilled

Sources & evidence

ORD record
ord-8b22782734554d2299b4166911bf5cef
Source dataset
uspto-grants-1991_05
Patent number
US05015473

Reaction notes

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