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Alkoxylation with 3-butyn-1-ol, followed by intramolecular Diels-Alder reaction, leads to a fused pyridine system, by a sequence analogous to that shown for 2-Chloropyrazine, A10108: Tetrahedron, 45, 803 (1989). For a similar sequence using the anion of an alkynylmalononitrile, see: Tetrahedron, 45, 5151 (1989). For synthesis of a benzofuropyridine by the cyclization of a 2-(alkynylphenoxy)pyrimidine, see: Tetrahedron, 45, 6511 (1989).• Organolithium reagents add to the 1,6-imine bond, giving, after aromatization with DDQ, 6-substituted 2-chloropyrimidines: J. Org. Chem., 53, 4137 (1988).