The reaction of three component isoquinoline and dimethyl acetylenedicarboxylate with pentachloropyridine

Heterocyclic compounds have occupied an important place in organic chemistry, and their derivatives have attracted considerable interests in recent years for their versatile properties in chemistry and medicine. In the context of the synthesis of novel families of polysubstituted heterocycles with useful biological properties and pharmaceutical applications, perfluorinated compounds, such as pentafluoropyridine, are important materials in organic chemistry and in the life science industries. Pentafluoro- and pentachloropyridines are most susceptible to nucleophilic attack by O-, S-, N-, and P-centered nucleophiles. Perhalogenated aromatic and heteroaromatic compounds are important starting materials for the synthesis of other heterocyclic. In this work, three-component reaction of isoquinoline, dimethyl acetylenedicarboxylate (DMAD) and perhalopyridines were investigated. Nucleophilic reaction of anion 3, derived from reaction of isoquinoline with DMAD, with perhaloropyridines gave corresponding products arising from the substitution of the most activated halogen at the 4-position of pyridine ring (Scheme 1). The structure of products were confirmed by IR, 1H-NMR, 13C-NMR spectroscopy data [1].