Hydroxyamine hydrochloride → 5-(Trifluoromethyl)isoxazol-3-ylamine

Dry methanol (220 ml) and 96% hydroxylamine hydrochloride (11.52 g, 0.159 mole) were added to trifluoroacetoacetonitrile (16.78 g, 0.122 mole) and the mixture was heated under reflux with stirring for 68 hours. Methanol was then evaporated under reduced pressure and, after addition of water (240 ml), a 48% solution of sodium hydroxide was added to the resulting residue to adjust to pH 11 or higher. The solution was extracted with methylene chloride and, after drying the extract with anhydrous sodium sulfate, the solvent was evaporated under reduced pressure to give the title compound (10.30 g, 55.2%) as little colored crystals, m.p. 57°-58° C., b.p. 66°-67° C./0.8 mmHg.

1. temperaturethe mixture was heated
2. temperatureunder reflux
3. customMethanol was then evaporated under reduced pressure
4. additionafter addition of water (240 ml)
5. additiona 48% solution of sodium hydroxide was added to the resulting residue
6. extractionThe solution was extracted with methylene chloride
7. customafter drying the
8. extractionextract with anhydrous sodium sulfate
9. customthe solvent was evaporated under reduced pressure

ORD-Eintrag

ord-46b7dd0638624d64a491071e96f39de2

Quelldatensatz

uspto-grants-1990_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04910326