Dimethylformamide → 3-Chloro-7-nitro-1,2-benzisothiazole

Participants

Reaction Steps

A 1 L four-neck flask equipped with a stirrer, a thermometer and a condenser tube was charged with 98.1 g (0.5 mol) of 7-nitro-1,2-benzisothiazol-3-one, 146.2 g (2 mol) of N,N-dimethylformamide and 500.0 g of chlorobenzene. While stirring, 119.0 g (1.0 mol) of thionyl chloride was added dropwise thereto at 80° to 90° C. over 1 hour, and the mixture was reacted at the same temperature for 3 hours. After terminating the reaction, the liquid reaction mixture was concentrated, and a crude product obtained was recrystallized from toluene to give 91.2 g (0.43 mol) of 3-chloro-7-nitro-1,2-benzisothiazole. The yield based on 7-nitro-1,2-benzisothiazol-3-one was 85%.

Provenance & Evidence