Ethyl 3-(4-methoxyphenyl)isoxazole-5-carboxylate → Ethyl 3-(4-hydroxyphenyl)isoxazole-5-carboxylate

HRID 524415Notes

Reaction equation

HRID 524415 reaction equation
C[O:2][C:3]1[CH:8]=[CH:7][C:6]([C:9]2[CH:13]=[C:12]([C:14]([O:16][CH2:17][CH3:18])=[O:15])[O:11][N:10]=2)=[CH:5][CH:4]=1>C(Cl)Cl.B(Br)(Br)Br>[OH:2][C:3]1[CH:4]=[CH:5][C:6]([C:9]2[CH:13]=[C:12]([C:14]([O:16][CH2:17][CH3:18])=[O:15])[O:11][N:10]=2)=[CH:7][CH:8]=1

Participants

4

Reactant 1

HCID 776513Ethyl 3-(4-methoxyphenyl)isoxazole-5-carboxylate

Product 1

HCID 136133842Ethyl 3-(4-hydroxyphenyl)isoxazole-5-carboxylateYield 74.3%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolvent2×HCID 25134Boron tribromideSolvent

Procedure

To a stirred solution of ethyl 3-(4-methoxyphenyl)isoxazole-5-carboxylate (1 g, 4.04 mmol, prepared according to literature method Tet. Lett 2009, 50(27), 3948-3951) in 8 mL DCM, Boron tribromide 1 M solution in DCM (8.0 mL, 8.08 mmol) was added dropwise at −78° C. After complete addition reaction mixture was allowed to warm slowly and further stirred for 16 hrs at RT. After completion of the reaction, solvent was removed under reduced pressure. The reaction mixture was diluted with ice cold water (20 mL) and extracted with ethyl acetate (3×50 mL). The combined organic layer was washed with water, brine and dried over sodium sulfate, filtered and concentrated under reduced pressure to get ethyl 3-(4-hydroxyphenyl)isoxazole-5-carboxylate (0.7 g).

Workup

  1. additionAfter complete addition reaction mixture
  2. temperatureto warm slowly
  3. customAfter completion of the reaction, solvent
  4. customwas removed under reduced pressure
  5. additionThe reaction mixture was diluted with ice cold water (20 mL)
  6. extractionextracted with ethyl acetate (3×50 mL)
  7. washThe combined organic layer was washed with water, brine
  8. dry with materialdried over sodium sulfate
  9. filtrationfiltered
  10. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-f8727927b39949abb06e4d09e49ae0ab
Source dataset
uspto-grants-2016_05
Patent number
US09340506B2

Reaction notes

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