Diphosphoniodiphosphene Formation by Transition Metal Insertion into a Triphosphenium Zwitterion

Treatment of two equivalents of the triphosphenium zwitterion L with sources of Ni0 and Pd0 form the mononuclear η2‐diphosphoniodiphosphene complexes 1 and 2. The reaction between L and [FeCp(CO)2]2 results in the binuclear μ‐η1:η1‐diphosphoniodiphosphene iron complex 3, which features an alternative bonding motif of the diphosphoniodiphosphene unit. The formation of these species has been confirmed by spectroscopic methods and single‐crystal X‐ray diffraction analysis, and their electronic structures have been elucidated using computational methods. A diphosphoniodiphosphene is unexpectedly formed by insertion of Ni0, Pd0, and FeI into the P−P bonds of a triphosphenium zwitterion, giving rise to structurally confirmed μ2‐bound monometallic or μ‐η1:η1‐bimetallic species.