反应详情

N-(3-Chloro-1H-indazol-5-yl)-3,4-dichlorobenzenesulfonamide can be obtained in the following way: a solution of 1.1 g of 3,4-dichlorobenzenesulfonyl chloride is added dropwise to a solution, cooled to 0° C. of 0.75 g of 5-amino-3-chloro-1H-indazole and of 14 ml of pyridine. After reacting for 10 minutes at a temperature in the region of 0° C. and 2 hours 30 minutes at a temperature in the region of 20° C., 50 ml of distilled water are added to the reaction medium. The medium is extracted with 50 ml and 25 ml of ethyl acetate. The organic phase is subsequently dried over magnesium sulfate, filtered and concentrated by evaporation under reduced pressure. The residue thus obtained is purified by chromatography on a silica column with a dichloromethane/methanol (99/1 by volume) mixture as eluent. The yellow oil thus obtained is again purified by chromatography on a silica column with dichloromethane as eluent. 0.08 g of N-(3-chloro-1H-indazol-5-yl)-3,4-dichlorobenzenesulfonamide is thus obtained in the form of a thick white oil (analysis C13H8Cl3N3O2S % calculated C, 41.46; H, 2.14; Cl, 28.24; N, 11.16; O, 8.50; S, 8.51. % found C, 41.43; H, 2.58; N, 10.81; S, 7.84).

1. additionare added to the reaction medium
2. extractionThe medium is extracted with 50 ml and 25 ml of ethyl acetate
3. dry with materialThe organic phase is subsequently dried over magnesium sulfate
4. filtrationfiltered
5. concentrationconcentrated by evaporation under reduced pressure
6. customThe residue thus obtained
7. customis purified by chromatography on a silica column with a dichloromethane/methanol (99/1 by volume) mixture as eluent
8. customThe yellow oil thus obtained
9. customis again purified by chromatography on a silica column with dichloromethane as eluent