反应详情

A mixture comprising 62 g (221 mmol) of 4-cyclopropylmethoxy-2-methyl-2H-indazole-3-sulfonamide, 120 ml of acetic acid and 120 ml of concentrated hydrochloric acid, was stirred at 80° C. for one hour. After concentrating acetic acid-hydrochloric acid, the mixture was poured into ice water. Crystals were collected by filtration and washed with water. Further, the crystals were washed with IPE and dried to obtain 35.1 g (yield: 70%) of the desired product. Melting point: 180°-181° C.

1. concentrationAfter concentrating acetic acid-hydrochloric acid
2. additionthe mixture was poured into ice water
3. filtrationCrystals were collected by filtration
4. washwashed with water
5. washFurther, the crystals were washed with IPE
6. customdried