Addition of Ammonia, Water, and Dihydrogen Across a Single Pd−Pd Bond

Pincer-supported Pd alkyl complexes (PNP)PdR undergo photochemical conversion to a dimeric (PNP)Pd−Pd(PNP) complex with a single Pd−Pd bond. Dissociation of the dimer into monomeric (PNP)Pd species is kinetically accessible thermally and photochemically. (PNP)Pd−Pd(PNP) reacts with ammonia, water, and dihydrogen by adding the H−X bond of the substrate (X = NH2, OH, H) across the Pd−Pd bond. For ammonia, this represents a rare example of conversion of NH3 to terminal hydride and amide ligands by a bimetallic complex.