Azine -oxides, activating effect reactions

The aza group activation effect in the oxidative amination of azines is less than that of the nitro group. As an illustration the reaction of 4-nitroquinoline and liquid ammonia in the presence of KMn04 produced 3-amino-4-nitroquinoline only in 86% yield [52]. Oxidative amination of 5-nitroquinoline gave 6-amino derivative in... 

The electron-withdrawing effect of typical azines makes chlorine substituents sufficiently reactive that they can participate in palladium-catalysed reactions, even at a pyridine / -position. " a-Activation can serve to allow regioselective reaction in the presence of a /3-halogen (cf. section 2.7.1.1, oxidative addition) and this should be contrasted with lithiation by exchange which shows the opposite regioselectivity. 

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