Hydrogen Splitting at a Single PIII-Center and Its Use for Hydrogenation

Main-group compounds that can mimic the behavior of the transition-metal (TM) complexes are of great interest due to their potential in TM-free catalysis. Here, we report the synthesis, isolation and full characterization of the geometrically constrained phosphenium cation with the 2,6-bis(o-carborano)pyridine pincer-type ligand. A preliminary reactivity study showed that this cation is capable of activating H−H bond by a formal oxidative addition to PIII cationic center, which is unprecedented reactivity for PIII-centers, producing new dihydrophosphonium cation. Remarkably, this new phosphenium cation is capable of catalyzing the hydrogenation reactions of C=C double bonds and fused aromatic systems.