反应详情

A mixture of 12.5 parts of ethyl 4-(1,2-benzisothiazol-3-yl)-1-piperazinecarboxylate and 187.5 parts of a hydrobromic acid solution 48% in water was stirred for 1.5 hours at reflux temperature. After evaporation, the residue was taken up in 2-propanol and the solvent was evaporated again. The residue was dissolved in methanol, evaporated again and stirred in 2-propanone. The product was filtered off and dried, yielding 11.5 parts (73%) of 3-(1-piperazinyl)-1,2-benzisothiazole dihydrobromide (int. 4).

1. temperatureat reflux temperature
2. customAfter evaporation
3. customthe solvent was evaporated again
4. dissolutionThe residue was dissolved in methanol
5. customevaporated again
6. stirringstirred in 2-propanone
7. filtrationThe product was filtered off
8. customdried