反应详情

A mixture of 5-phenyl-4-(trifluoromethyl)isoxazole-3-carbaldehyde (step B, 0.415 g, 1.721 mmol), hydroxylamine hydrochloride (0.179 g, 2.58 mmol), and sodium acetate (0.212 g, 2.58 mmol) in methanol (5 mL) was heated at reflux for 45 min. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The residue was suspended in water (10 mL), and the solid was collected by vacuum filtration, washed with water (2×5 mL), and dried overnight under reduced pressure to give 5-phenyl-4-(trifluoromethyl)isoxazole-3-carbaldehyde oxime (0.360 g, 1.41 mmol, 82% yield). The compound had an HPLC ret. time=2.43 min. (condition A); LC/MS M+1=256.9.

1. temperaturewas heated
2. temperatureat reflux for 45 min
3. concentrationconcentrated under reduced pressure
4. filtrationthe solid was collected by vacuum filtration
5. washwashed with water (2×5 mL)
6. customdried overnight under reduced pressure