Here, we report the synthesis, isolation and full characterization of the ambiphilic, geometrically constrained phosphenium cation (1 + ) with the 2,6-bis(o-carborano)pyridine pincertype ligand (2) (Fig. ). The reaction of 1 + with dihydrogen produces the dihydrophosphonium cation (1 + -H2) via a formal oxidative addition of H-H bond to P III -center in 1 + (Fig. ). Density functional theory (DFT) calculations of the possible mechanism of this activation (Fig. ) as well as the use of 1 + in the catalytic hydrogenation reactions of C=C double bonds and fused aromatic systems are also described (Fig. ).