Diazines, Chichibabin amination reaction

In 1972, Zoltewicz and Helmick reported the first evidence of anionic o-adducts in the Chichibabin amination reaction. The parent diazines a-adduct complex (pyrimidine, pyridazine and pyrazine) in KNH2-NH3/KMn04 (at low temperature 0 to 0 °C) are shown below. Despite the fact that the parent pyrimidine has three possible amination spots, 18 is the adduct formed and similarly for pyridazine and pyrazine, adducts 19 and 20 are formed under the aforementioned conditions. The regio-chemical outcome changes when these rings are substituted. 

The examples shown below are illustrative of the many easy nucleophilic additions to the polyaza-azines The reaction of 1,2,4,5-tetrazine with simple amines can be contrasted with the requirement for sodamide (Chichibabin reaction) for the diazines and pyridine. 

The examples shown below are illustrative of the many easy nucleophilic additions to the polyaza-azines the reaction of 1,2,4,5-tetrazine with simple amines can be contrasted with the requirement for sodamide (Chichibabin reaction) for the diazines and pyridine. The easy addition at C-5 of 1,2,4-tri-azines is shown by the VNS reaction of the 3-methylthio-derivatives in the absence of activating groups the ready displacement of methylthio from the same compound is also indicative. ... 

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