Carbenes and nitrenes in heterocyclic chemistry, intramolecular reactions

Chemistry of Dihydroazines, 38, 1. Wentrup, C., Carbenes and Nitrenes in Heterocyclic Chemistry Intramolecular Reactions, 28, 231. 

Carbenes and Nitrenes in Heterocyclic Chemistry Intramolecular Reactions... 

C. Wentrup, Carbenes and Nitrenes in Heterocyclic Chemistry. Intramolecular Reactions , Adv. Heterocycl. Synth, 1981, 28, 232. 

The chemistry of short-lived intermediates is difficult to study because usually the species cannot be directly observed under the reaction conditions. Much of the knowledge is therefore obtained by deduction from product studies. In the present review we are dealing mainly with intramolecular gas-phase reactions, and the carbenes and nitrenes in question are most frequently generated from diazo-compounds and azides (or in heterocyclic systems valence isomers thereof, triazo-loazines and tetrazoloazines). It is known that diazo-compounds and azides deld carbenes and nitrenes, respectively, by low-temperature photolysis i>2). However, the cycloheptatrienylidenes and azepinylidenes invoked in many reaction mechanisms have not yet been observed by any spectroscopic means, and their existence is deduced exclusively from their chemistry. 

Carbenes and nitrenes, intramolecular reactions in heterocyclic chemistry ... 

Natural products, synthesis via aziridine intermediates, 39, 181 New developments in the chemistry of oxazolones, 21, 175 Nitration of phenyl-substituted heterocycles, 58, 215 Nitrenes, carbenes and, intramolecular reactions of, 28, 231... 

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