Hydroxyamine hydrochloride → 4-Fluoro-2-(5-isoxazolyl)phenol

HRID 1581796Notes

Reaction equation

HRID 1581796 reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][CH:7]=[CH:6][C:5]2=[O:12].Cl.[NH2:14]O>C(O)C>[F:1][C:2]1[CH:11]=[CH:10][C:9]([OH:8])=[C:4]([C:5]2[O:12][N:14]=[CH:7][CH:6]=2)[CH:3]=1

Participants

4

Reactant 2

HCID 443297Hydroxyamine hydrochlorideHCID 6888926-Fluorochromone

Product 1

HCID 27589854-Fluoro-2-(5-isoxazolyl)phenolYield 12%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

The product from above (6-fluorochromen-4-one (5.25 g, 32.0 mmol) and hydroxylamine hydrochloride (4.65 g, 67.2 mmol) are dissolved in ethanol (180 ml) and the resulting mixture is heated to reflux. The reaction is allowed to stir for 18 hours before cooling and concentrating. The residue is is taken up in toluene and filtered to give 690 mg of 4-fluoro-2-(isoxazol-5-yl)phenol and from the filtrate 594 mg of 4-fluoro-2-(isoxazol-3-yl)phenol. These phenolic products are separately reacted with (2S)-glycidyl 3-nitrobenzenesulfonate substantially as described for Epoxide 1 to yield the title epoxides.

Workup

  1. temperaturethe resulting mixture is heated to reflux
  2. temperaturebefore cooling
  3. concentrationconcentrating
  4. filtrationfiltered

Sources & evidence

ORD record
ord-c9271fe196e941a6a6944f0acbdb9d7d
Source dataset
uspto-grants-2004_05
Patent number
US06730792B2

Reaction notes

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