Regioselective, One-Pot Syntheses of Symmetrically and Unsymmetrically Halogenated 2′,6′-Bispyrazolylpyridines

Abstract

A series of regio-selectively 3′-, 4-, 4′-, 4′′-, and 5′-halogenated heterocyclic 2′,6′-bispyrazolylpyridine derivatives was prepared by a direct halogenation reaction in a simple, one-pot synthesis in good to excellent yield (in gram scale). This methodology yielded several symmetrically and asymmetrically substituted mono-, di-, tri-, and tetra-halo (bromo and iodo) substituted 2′,6′-bispyrazolylpyridine cores, which may serve as potential intermediates for several metal-catalyzed coupling reactions.

Key words

heterocycles - halogenation - halogenated 2,6-bis(pyrazol-1-yl)pyridine - N-ligands - pyridines

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