The preparation of 2H‐1,2,3‐benzothiadiazine‐1,1‐dioxides, 11H‐11a‐dihydrobenzimidazo[1,2‐b] [1,2] benzisothiazole‐5,5‐dioxides, 6H‐dibenzo[c,g] [1,2,5] thiadiazocine‐5,5‐dioxides and 5H‐Dibenzo[c,g] [1,2,6] thiadiazocine‐6,6‐dioxides

Abstract o ‐Benzoylbenzenesulfonyl chlorides (I) were prepared conveniently from aminobenzophenones by diazotization followed by reaction with sulphur dioxide in the presence of Cu + , according to the general method of Meerwein. Reaction of the sulfonyl chlorides with hydrazine led to 4‐phenyl‐2 H ... View More