The reaction of 4,5-dichloro-1,2,3-dithiazolium chloride with 2-(phenylsulfonyl)acetonitrile (1 equiv) in the presence of pyridine (2 equiv) gave S-(3-chloro-5-cyanoisothiazol-4-yl)benzenesulfonothioate and (Z)-2-(4-chloro-5H-1,2,3-dithiazol-5-ylidene)-2-(phenylsulfonyl)acetonitrile in 19% and 23% yield, respectively. The compounds were fully characterized and the mechanistic rationale is proposed for the formation of the benzensulfonate.