Nucleophiles, reactions with 1,2,4-triazines review

There have been reviews of nucleophilic substitution103 and of deoxidative nucleophilic substitution 104 in heterocyclic A -oxidcs. Stable carbon-carbon-bonded adducts, such as (22), have been reported from the reactions of 6-phenyl-1,2,4-triazine 4-oxides with phenols oxidation of the adducts may be achieved by reaction with potassium permanganate in acetone.105... 

When a substituent with a good leaving ability is present in the 1,2,4-triazine ring at C-3, C-5, and/or C-6, nucleophilic substitution reactions can occur. Many SN reactions are described in the literature. In Sections IV,A-C, examples of displacement of one, two, and three nucleofugic groups are discussed. In this article, the displacement reactions are not exhaustingly reviewed. We show only the fundamental reaction features, their value, and scope for application in the synthesis of functionalized 1,2,4-triazine derivatives. As far as the mechanisms of nucleophilic sub-... 

---