反应详情

3-Ethyl-5-acetylaminoisoxazole (1) (1.98 g) was dissolved in acetic acid (15 ml), chlorine-tetrachloromethane (18 ml, containing 1.09 g of chlorine) was added thereto under stirring at room temperature and after addition of water the mixture was extracted with chloroform after 5 minutes. The extract was washed with water, dried over sodium sulfate and evaporated. The resulting crystalline residue was recrystallized from ether/hexane to give 3-ethyl-4-chloro-5-acetylaminoisoxazole (2) (1.86 g), mp. 113°-114° C.

1. extractionwas extracted with chloroform after 5 minutes
2. washThe extract was washed with water
3. dry with materialdried over sodium sulfate
4. customevaporated
5. customThe resulting crystalline residue was recrystallized from ether/hexane