反应详情

150.6 g of 3-methoxy-4-chloro-1,2,5-thiadiazole (1 mole) were suspended in 156.26 g of dimethyl sulfoxide (2 mole) and 258.31 g of sulfanilamide (1.5 mole) and 414.63 g of potassium carbonate (3 mole) were then added. The mixture was kept at 70° C. for 48 hours while stirring. 600 ml of water were then added, the mixture was cooled to ambient temperature and adjusted to pH 1.5 with concentrated hydrochloric acid. The precipitated crystallized material was filtered off, washed with water and dried. A yield of 271.1 g of crude 3-methoxy-4-(4'-aminobenzenesulfonamido)-1,2,5-thiadiazole (94.67% of theory), melting point 138°-146° C., was obtained.

1. customThe precipitated crystallized material
2. filtrationwas filtered off
3. washwashed with water
4. customdried