Heteroarylnitrenium ions

In some cases, the initial adduct can combine with an additional nucleophile to give a diadduct. This process is particularly likely when the driving force for aro-matization of the monoadduct is weak or absent. For example, Novak has shown that heteroarylnitrenium ion 85 is trapped at first by water and then by an additional nucleophile to give the diadduct 87 (Fig. 13.45). Likewise, Bose et al. reported the dihydroxylation of the nitrenium ion 88 derived from stilbene... 

This process has not been studied in detail. It has been shown that diphenylnitren-ium ion reacts with various hydrocarbons and metal hydrides to give diphenyl amine. An analysis of the rate constants for these processes showed that the reaction was most likely a hydride transfer, rather than a hydrogen atom transfer (Fig. 13.56). Novak and Kazerani found a similar process in their study of the decay reaction of heteroarylnitrenium ions. 

Figure 13.74. Reactions of heteroarylnitrenium ions with guanosine.

Reactions with carbon, nitrogen and sulfur nucleophiles 214 Direct observation of nitrenium ions acid-base chemistry and singlet-triplet chemistry 227 Heteroarylnitrenium ions 238 Calculations 244... 

Research into heteroarylnitrenium ions has been spurred by their apparent involvement in the carcinogenicity of heterocyclic arylamines and the antibiotic effects of 2-nitroimidazoles against anaerobic bacteria and protozoa, and by theoretical considerations. ... 

Chemistry of heteroarylnitrenium ions. Research in this area has been spurred by the apparent importance of heterocyclic amines produced during the cooking of protein-containing foods as a ubiquitous class of human carcinogens. This chemistry has been under investigation for only a short period of time. 

SuUivan, M. B. and Cramer, C. J., Quantum chemical analysis of heteroarylnitrenium ions and mechanisms for their self-destruction, /. Am. Chem. Soc., 122, 5588, 2000. 

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