Nitrenes sulfonylnitrenes

Sulfonyl nitrenes react with benzene to produce appreciable yields of aromatic substitution products. The nitrene thermally generated in benzene from 229 gives a monosubstitution product. When the reaction is carried out in mesitylene as a solvent, the two sulfonylnitrenes react with mesitylene to afford 230 (equation 140)135. 

With sulfonylnitrenes, additions to double bonds are very rare. The reason is that addition of the sulfonylazide to the double bond normally is much faster than azide decomposition. Another explanation is double-bond participation in the nitrogen elimination where no free nitrene is involved. 

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... 

Abramovitch and co-workers,122 investigating the chemistry of aryl-nitrenes and sulfonylnitrenes, thermolyzed biarylsulfonyl azides (136) which at 120°C produced 6H-dibenzo[c,e] [ 1,2]thiazine 5,5-dioxide (138) (80%) via the proposed intermediate 137 (Eq. 34). N-Alkylation of 138 with... 

Nltrenes (s. a. Sulfonylnitrenes) N-heterocyclics via review 18,338 suppl. 27 review 26, 630 N-Nitrenes, review 23, 381 suppl. 27... 

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