The Synthesis of Polynitrile Aromatic and Oligopyridine Ligands via Palladium-Catalyzed Cyanation of Aryl Halides

Modification of Beller's palladium-catalyzed cyanation procedure for simple aromatic halides leads to a versatile and rapid route to complex multi-nitrile aryl and oligopyridyl ligands that improves on known literature methods. By heating the reagents in the high boiling solvent mesitylene to reflux temperatures at ambient pressure, we have observed the conversion of halogenated precursors to the corresponding nitrile compounds. The resulting compounds can be precipitated from CH 2 Cl 2 solutions of the reaction mixtures and isolated as pure compounds in moderate to high yields. The current approach offers a safer alternative to the pressure tube method, as it does not involve the use of KCN at high pressures.