Hydroxylamine HCl → 6-Fluoro-3-methyl-1,2-benzoxazole

HRID 1673662Notes

Reaction equation

HRID 1673662 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([C:8](=O)[CH3:9])=[C:4]([OH:11])[CH:3]=1.[Cl-].O[NH3+:14].C([O-])(=O)C.[Na+]>CO>[F:1][C:2]1[CH:7]=[CH:6][C:5]2[C:8]([CH3:9])=[N:14][O:11][C:4]=2[CH:3]=1

Participants

5

Conditions

Temperature
60 °C

Procedure

A mixture of 1-(4-fluoro-2-hydroxyphenyl)ethanone (20 g), hydroxyammonium chloride (18.1 g), sodium acetate (16 g) and methanol (500 mL) was stirred at 60° C. for 1 hr. The reaction mixture was added to ice water, and the obtained crystallized product was collected by filtration and dissolved in tetrahydrofuran (400 mL). N,N′-carbonyldiimidazole (22.5 g) and then a solution of triethylamine (22.3 mL) in tetrahydrofuran (100 mL) were added, and the mixture was stirred at 70° C. for 1 hr. The reaction mixture was diluted with diethyl ether, washed with water and then with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure to give the title compound as colorless crystals (13.7 g, 70%).

Workup

  1. customthe obtained crystallized product
  2. filtrationwas collected by filtration
  3. dissolutiondissolved in tetrahydrofuran (400 mL)
  4. additionN,N′-carbonyldiimidazole (22.5 g) and then a solution of triethylamine (22.3 mL) in tetrahydrofuran (100 mL) were added
  5. stirringthe mixture was stirred at 70° C. for 1 hr
  6. additionThe reaction mixture was diluted with diethyl ether
  7. washwashed with water
  8. dry with materialwith saturated brine, and dried over anhydrous magnesium sulfate
  9. customThe solvent was evaporated under reduced pressure

Sources & evidence

ORD record
ord-645a68f5582b4249aad5b3522cc3dd3d
Source dataset
uspto-grants-2011_08
Patent number
US07998968B2

Reaction notes

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