%0 Journal Article
%T Synthesis and Intramolecular [4+2] Cycloaddition Reactions of 4-Pyridazinecarbonitriles with Alkyne Side Chains
%A G¨šnther F¨šlep
%A Norbert Haider
%J Molecules
%D 1998
%I MDPI AG
%R 10.3390/30100010
%X The preparation of a series of new 3-(alkynyl-X)-substituted 4-pyridazinecarbonitriles 2-5 (X = O, NH) is described. The compounds are shown to undergo thermally induced intramolecular Diels-Alder reactions with inverse electron demand, affording the fused benzonitriles 6-8. Incorporation of a 1,2-phenylene unit into the side chain, as in the case of compounds 10 and 13, results in a more favorable conformation of the dienophilic substructure and thus to a pronounced acceleration of the [4+2] cycloaddition reaction.
%K [4+2] Cycloaddition
%K inverse-electron-demand Diels-Alder reaction
%K 4-pyridazinecarbonitriles
%U http://www.mdpi.com/1420-3049/3/1/10