One‐Step Synthesis of Symmetrically Substituted 2,6‐Bis(pyrazol‐1‐yl)pyridine Systems

Abstract
A one‐pot synthetic route that allows functionalization of the 2,6‐bis(pyrazol‐1‐yl)pyridine backbone in the 4‐ and 4″‐pyrazole positions by direct H(4)‐pyrazole halogen exchange is described. The diiodo derivative in particular provides easy access to additional functionalities through both Sonogashira and Grignard exchange reactions. These synthons represent optimal building blocks for the extension of the chelating core and for the assembly of rigid organic and metalloorganic nanostructures. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)