Poly cyclic compounds

Nitration and aromatic reactivity D The nitration of hi- and poly-cyclic compounds... 

Part 2 (Volumes 2 and 3) deals with mono- and poly-cyclic compounds with one or more six-membered heterocyclic ring, with nitrogen, oxygen and sulfur as the heteroatoms. Volume 2 contains the six-membered rings with one nitrogen atom (Part 2A) and Volume... 

Electron-deficient heteroaromatic systems such as 1,2,4-triazines and 1,2,4,5-tetrazines easily undergo inverse electron demand Diels-Alder (lEDDA) reactions. 1,2-Diazines are less reactive, but pyridazines and phthalazines with strong electron-withdrawing substituents are sufficiently reactive to react as electron-deficient diazadienes with electron-rich dienophiles. Several examples have been discussed in CHEC-II(1996) <1996CHEC-II(6)1>. This lEDDA reaction followed by a retro-Diels-Alder loss of N2 remains a very powerful tool for the synthesis of (poly)cyclic compounds. 

In this context, it should be mentioned that free cations in suitable solvents can be used as templates for the synthesis of macro(poly)cyclic compounds e.g. catenanes). Such template-based syntheses are mediated by slightly solvated metal cations, which assemble the reaction partners as ligands, allowing them to easily react with each other the desired product is obtained after removal of the template for a review, see reference [845]. 

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