Thionyl Chloride → Pseudosaccharin chloride

Participants

Reaction Steps

100 g (545 mM) of benzisothiazole-1,1-dioxide 100 ml. of thionyl chloride, 4 ml. of dimethylformamide (catalyst) and 400 ml. of dioxane are refluxed overnight. Thionyl chloride (50 ml.) and dimethylformamide (1 ml.) are added to the reaction mixture which is again refluxed overnight. The reaction mixture is evaporated to dryness and the residue recrystallized from toluene to obtain 73.4 g of 3-chloro-1,2-benzisothiazole-1,1-dioxide, m.p. 140°-145°.

Provenance & Evidence