Iron–cobalt-catalyzed heterotrimerization of alkynes and nitriles to polyfunctionalized pyridines†
Abstract
Based on the reactivity of half-sandwich complexes [Cp*Fe(NCMe)3]PF6 and Cp*Co(1,2-Ph2PC6H4NH), (Cp* = Me5C5−), the iron(II)–cobalt(II) co-catalysis of the cycloaddition of alkynes to nitriles under mild reaction conditions has been studied. This method enables the synthesis of polysubstituted pyridines in a single step, and is especially valuable for the preparation of 2,3,4,5,6-pentafunctionalized pyridines.