Azines reactivity

The relation of the activation by a nitro group to that by an azine-nitrogen in various bicyclic positions provides information in support of that available from studies of azines and forms the basis for certain predictions of azine reactivity. The data tabulated in Section IV, A, 2 also provide a few comparisons of leaving groups, nucleophiles, and deactivating and activating substituents (cf. Sections II, E and III, A, 2). 

The 8jjAr2 mechanism in reactions at heteroaromatic carbon atoms does not have the same kind of experimental support as it does in carbocyclio reactions. However, there appears to be no contrary evidence in these demonstrably bimoleoular substitutions, and, therefore, we use it herein as the basis for interpreting azine reactivity. 

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