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
2. additionhydrochloric acid, the 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