反应详情

5.0 g of 7-nitro-4-hydroxy-1,2-benzisothiazole, in a mixture of 50 ml of acetic anhydride, 10 ml of acetic acid and 50 mg of a 5% strength palladium-on-charcoal catalyst, are left for 10 hours at 60° C. under 100 bars hydrogen pressure. After the mixture has cooled, the catalyst is filtered off, the filtrate is concentrated under reduced pressure and the partially crystalline crude product is recrystallized from acetic anhydride. 4.2 g (67% of theory) of 7-acetamino-4-acetoxy-1,2-benzisothiazole of melting point 215°-216° C. are obtained.

1. temperatureAfter the mixture has cooled
2. filtrationthe catalyst is filtered off
3. concentrationthe filtrate is concentrated under reduced pressure
4. customthe partially crystalline crude product is recrystallized from acetic anhydride