Water → Ethyl 1,2-benzoxazole-3-carboxylate

HRID 1721813Notes

Reaction equation

HRID 1721813 reaction equation
[N+]([C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=1[C:10](=[N:16][OH:17])[C:11]([O:13][CH2:14][CH3:15])=[O:12])([O-])=O.[H-].[Na+].O>COCCOCCOC>[O:17]1[C:4]2[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=2[C:10]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[N:16]1

Participants

5

Reactant 3

HCID 962WaterHCID 24758Sodium hydrideHCID 53403224Ethyl α-(hydroxyimino)-2-nitrobenzeneacetate

Product 1

HCID 14177940Ethyl 1,2-benzoxazole-3-carboxylate

Reagents, catalysts & solvents 1

HCID 8150DiglymeSolvent2×

Conditions

Temperature
0 °C

Procedure

20 g of 3A was dissolved in 100 ml of diglyme and the solution was added dropwise to a vigorously stirred mixture of 2.5 g of sodium hydride and 100 ml of diglyme, under nitrogen at room temperature. The mixture was heated slowly to and held at 150° C. for 6 hours, then cooled, mixed with 200 ml of water and extracted with ether. The extract was dried and stripped of solvent. The residue was distilled in a Kugelrohr apparatus (60° C./0.05 Torr); the resulting residue was dissolved in warm petroleum ether, the solution was chilled to 0° C., and the solid phase was collected and dried, to give ethyl 3-benzisoxazolylcarboxylate (3B), as a white solid, m.p.: 53°-55° C.

Workup

  1. temperatureThe mixture was heated slowly to and
  2. temperaturecooled
  3. extractionextracted with ether
  4. customThe extract was dried
  5. distillationThe residue was distilled in a Kugelrohr apparatus (60° C./0.05 Torr)
  6. dissolutionthe resulting residue was dissolved in warm petroleum ether
  7. customthe solid phase was collected
  8. customdried

Sources & evidence

ORD record
ord-b80a918bdd2f47aa8cfb05baaec85555
Source dataset
uspto-grants-1989_08
Patent number
US04853027

Reaction notes

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