Nitrenes and nitrenium ions

X 10 M Combined with the experimental pK, of 14.8 in the solvent employed in this study (20% CH3CN/H2O), and the requirement that koH /kv, — KJKvj, these rate constants lead to a calculated pK of 75n of 16.0. " Although the parent N-arylnitrenium ion 75a cannot be directly detected in LFP studies, the pH dependence of yields of nitrene and nitrenium-ion-derived products led to the conclusion that the pKg of 75a s=12.4. ... 

Nitrenes ([NH]) are the neutral nitrogen analogs of carbenes, while nitrenium ions ([NH2]+) are isoelectronic to carbenes. Many of the reactions which are observed for carbenes have parallels in nitrene and nitrenium ion chemistry. Like carbenes, nitrenes and nitrenium ions can exist in both singlet and triplet states. There are some interesting divergences in chemical properties and in the effects of substituents, however, which are readily understood on the basis of orbital interaction diagrams. 

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