Synthesis and reactivity of dinuclear complexes containing η²-phenyl-metal interactions. Crystal structures of [NBu₄][(C₆F₅)₃Pt{μ-Ph ₂PCH₂PPh(eta;²-Ph)}Pt(C₆F ₅)₂]

Reaction between [NBu₄][Pt(C₆F₅)₃(dppm-? ¹P)] and cis-[M(C₆X₅)₂(thf)₂] (M = Pt, Pd; X = F, Cl; thf = tetrahydrofuran) leads to dinuclear derivatives with dppm ligands bridging two metal centers: [NBu₄][(C₆F₅)₃-Pt{µ-Ph ₂PCH₂PPh(?²-Ph)}M(C₆X ₅)2] [X = F, M = Pt (1), M = Pd (2); X = Cl, M = Pt (3), M = Pd (4)]. The structural characterization of complex 1 by single-crystal X-ray diffraction (orthorhombic system, space group Fdd2, with a = 26.520(7) Å, b = 83.69(3) Å, c = 13.835(5) Å, V = 30706(11) ų, and Z = 16) reveals two square-planar platinum(II) fragments sharing a dppm ligand with a ?²-phenyl-platinum interaction between a phenyl ring of the dppm ligand and one platinum center. This weak ?²-phenyl-platinum interaction can be easily displaced by addition of ligands such as CO (giving complex 5), PPh₃ (6), or p-toluidine (7). The structure of 5 was determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group Pn, with a = 12.259(2) Å,b = 16.375(3) Å, c = 18.851(4) Å, ß = 100.99(3)°, V = 3714.8 A°³, and Z = 2. The complex consists of two square-planar platinum(II) fragments with the dppm ligand acting as a conventional bridge. © 1999 American Chemical Society.