Advances in the Negishi Coupling

Background Palladium-catalyzed coupling reactions have now become part of a common set of reactions that chemists have to generate complex molecules. A particularly interesting version of this general reaction is the Negishi coupling. [ 1 ] Two steps are involved: the formation of an organozinc reagent, and the coupling reaction itself in which the preformed organozinc undergoes a transmetallation in the catalytic cycle (Scheme 1). The discovery that zinc-derived reagents readily take part in palladium coupling reactions has provided a very mild and extremely efficient way to create carbon-carbon bonds from highly functionalized precursors. The two pivotal steps of the Negishi coupling have benefited from the recent developments in organozinc preparation and new ligands incorporated into the palladium catalyst.