An investigation into Pd-catalyzed C−N cross-coupling reactions of aryl iodides is described. NaI is shown to have a significant inhibitory effect on these processes. By switching to a solvent system in which the iodide byproduct was insoluble, reactions of aryl iodides were accomplished with the same efficiencies as aryl chlorides and bromides. Using catalyst systems based on certain biarylphosphine ligands, aryl iodides were successfully reacted with an array of primary and secondary amines in high yields. Lastly, reactions of heteroarylamines and heteroaryliodides were also conducted in high yields.
“An Efficient Process for Pd-Catalyzed C−N Cross-Coupling Reactions of Aryl Iodides: Insight Into Controlling Factors”, J. Am. Chem. Soc., 2009, 131(16), 5766-5768.