反应详情

19 g of methyl 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxylate is placed in 200 ml of CCl4 and 8.54 g of NBS and then 1 g of benzoyl peroxide are added, heating under reflux overnight. On returning to RT, the precipitate that forms is filtered and washed with CCl4. All of the filtrate is evaporated, then taken up in AcOEt and washed with saturated NaCl solution (twice). It is dried over MgSO4 and evaporated. The expected compound crystallizes in iso ether, it is filtered and dried to obtain 19.4 g of the expected compound.

1. temperatureheating
2. temperatureunder reflux overnight
3. customOn returning to RT
4. filtrationthe precipitate that forms is filtered
5. washwashed with CCl4
6. customAll of the filtrate is evaporated
7. washwashed with saturated NaCl solution (twice)
8. dry with materialIt is dried over MgSO4
9. customevaporated
10. customThe expected compound crystallizes in iso ether, it
11. filtrationis filtered
12. customdried