Metal-Catalyzed P–C Bond Formation via P–H Oxidative Addition: Fundamentals and Recent Advances

Metal-catalyzed addition of P–H bonds to alkenes, alkynes, and other unsaturated substrates in hydrophosphination and related reactions is an atom-economical approach to valuable organophosphorus compounds. Understanding the mechanisms of these processes may enable synthetic improvements and development of new reactions. The first step in several catalytic cycles is P–H oxidative addition to yield intermediate metal hydride complexes bearing M–P bonds. P–C bond formation may occur via substrate insertion into the M–H bond, followed by P–C reductive elimination, or by insertion into the M–P bond and C–H reductive elimination. In an alternative outer-sphere process, nucleophilic attack of a metal–phosphido (M–PR2) group on an unsaturated substrate and proton transfer involving the metal hydride yields the product. This Perspective reviews the mechanistic possibilities, with a focus on the P–H activation step, and recent progress in developing novel catalytic transformations involving P–C bond formation.