反应详情

A suspension of 3,5-difluoroaniline (10 g, 0.0617 mol) in water (40 ml) and 37 per cent strength hydrochloric acid (5.3 ml, 0.066 mol) was added to a solution of chloral hydrate (11 g, 0.066 mol) and sodium sulfate (70 g) in water (240 ml). A solution of hydroxylamine hydrochloride (13.5 g, 0.195 mmol) in water (60 ml) was added to this mixture. The reaction mixture was boiled under reflux for 1 h, during which a clear reaction solution formed, from which a reaction product already precipitated out when hot. The mixture was stirred at room temperature for 16 h and, after filtration and washing with water (3×50 ml), the desired oxime was obtained in a yield of 84% (12.1 g) with a melting point of 179° C. as a yellow solid.

1. temperatureunder reflux for 1 h, during which a clear reaction solution
2. customformed, from which a reaction product
3. customalready precipitated out when hot
4. filtrationafter filtration
5. washwashing with water (3×50 ml)