反应详情

A suspension of 7-chloro-3-methylsulfanyl-4H-1,2,4-benzothiadiazine 1,1-dioxide (0.5 g) in an aqueous solution of sodium hydrogen carbonate (0.22 g/25 mL) was supplemented dropwise with 2M NaOH until complete dissolution. Liquid bromine (0.1 mL) was added under stirring at room temperature. After 10 min., the resulting suspension was adjusted to pH 2-3 with 6N HCl and the insoluble material was collected by filtration and washed with water. The white precipitate was suspended in methanol (20 mL), stirred for 1 h and then collected by filtration, washed with methanol and dried (yield: 0.45 g); m.p. 260-261° C.

1. filtrationthe insoluble material was collected by filtration
2. washwashed with water
3. stirringstirred for 1 h
4. filtrationcollected by filtration
5. washwashed with methanol
6. customdried (yield: 0.45 g)