In nitrene formation

The thermolysis of o-azidosulfonyl-f-anilines resulted in nitrene formation and trapping of the nitrene by the adjacent amino nitrogen to give a zwitterionic thiadiazole dioxide 108 from the dimethyl- or 6-membered heterocyclic ring precursor. The ring-opened/dealkylated derivative 109 was formed from other dialkyl or ring systems (Scheme 36) [74 JCS(P1)2451]. The pyrrolidino azide was unique in giving no thiadiazole, but rather products derived from a sulfonylnitrene precursor, perhaps in... 

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