反应详情

A mixture of 57.6 g of 2-chlorovinyl 2,4-dichloro-5-fluoro-phenyl ketone, 16.4 g of hydroxylamine hydrochloride and 150 ml of methanol is heated at the boiling point under reflux for 6 hours, a precipitate separating out after about one hour. This is filtered off cold with suction, washed with a little methanol and dried at 50° C. in vacuo. 33.3 g (63.2%) of 5-(2,4-dichloro-5-fluorophenyl)-isoxazole of melting point 112°-113° C., which, according to investigations by NMR spectroscopy, contains about 6 mole % of an isomer, are obtained.

1. temperatureis heated at the boiling point
2. temperatureunder reflux for 6 hours
3. customa precipitate separating out after about one hour
4. filtrationThis is filtered off cold with suction
5. washwashed with a little methanol
6. customdried at 50° C. in vacuo
7. customare obtained