反应详情

4-Chloro-2-fluoro-5-hydroxyphenylhydrazine (0.5 g), 2-acetylcyclohexanone (0.4 g) and a catalytic amount of acetic acid were admixed with xylene (15 ml), and the resultant mixture was heated under reflux for 5 hours while removing water. After cooling, the mixture was concentrated, and the residue was purified by silica gel column chromatography to obtain 0.7 g of 2-(4-chloro-2-fluoro-5-hydroxyphenyl)-3-methyl-4,5,6,7-tetrahydro-2H-indazole. m.p., 188.5°-190° C.

1. temperatureunder reflux for 5 hours
2. customwhile removing water
3. temperatureAfter cooling
4. concentrationthe mixture was concentrated
5. customthe residue was purified by silica gel column chromatography