dppp

dppp, short for 1,3-bis(diphenylphosphino)propane, is a bidentate phosphine ligand widely used in coordination chemistry and homogeneous catalysis. It consists of two diphenylphosphino groups linked by a flexible three-carbon (propane) backbone, allowing it to chelate transition metal centers through its two phosphorus donor atoms.

In coordination chemistry, dppp forms chelate complexes with a range of metals, including palladium, platinum, nickel, rhodium, and ruthenium. The two phosphine donors bind to a metal center to create relatively stable, four-coordinate complexes of the type M(dppp)Ln, where L denotes other ligands or halides. The bite angle, the angle between the two M–P bonds, is influenced by the backbone and metal and is typically in the vicinity of 90 to 110 degrees. This bite angle can affect the geometry, electronic environment, and catalytic performance of the metal center.

Applications of dppp are most prominent in homogeneous catalysis. It is employed in palladium- and nickel-catalyzed cross-coupling reactions such as Suzuki-Miyaura, Heck, and Sonogashira couplings, where the ligand helps stabilize reactive intermediates and can influence reaction rates and selectivity. Dppp is valued for its relatively straightforward synthesis, robustness under a variety of reaction conditions, and the ability to tune catalytic properties by substituting the phenyl rings or combining with different metals.

Dppp is commercially available and can be used in preformed metal complexes or introduced in situ. Related ligands with longer or shorter backbones, such as dppe and dppb, offer alternative bite angles and steric profiles for specific catalytic applications.