Flash Communication: Reaction of a Yttrium Phosphide Complex with Carbon Dioxide Gives a Paddlewheel-Like Phosphinocarboxylate

The insertion of carbon dioxide into rare earth metal–phosphorus bonds is underexplored compared to many other rare earth metal–ligand σ-bonds. Treatment of a C 6 D 6 solution of the dimeric yttrium bis(trimethylsilyl)phosphide complex [Y(P″) 2 (μ-P″)] 2 ( 1-Y; P″ = {P(SiMe 3 ) 2 } − ) with 1 atm carbon dioxide resulted in rapid conversion to the dimeric hexaphosphinocarboxylate product [Y{O 2 C(P″)-κ 2 O, O ′}{μ-O 2 C(P″)-1κ O;2κ O ′}{μ-O 2 C(P″)-1:2κ 2 O;1κ O ′}] 2 ( 2-Y ), which was characterized by single crystal X-ray diffraction, multinuclear NMR and ATR-IR spectroscopy, and elemental analysis. Complex 2-Y has a paddlewheel-like structure, with one bidentate bis(silyl)phosphinocarboxylate terminally bound at each yttrium center and the other four ligands bridging these ions with two distinct binding modes. This dimeric formulation persists in solution, with dynamic averaging of bridging ligand environments.