Bicyclic dinuclear tris-(ditopic diphosphane) complexes of zerovalent group 10 metals†

Selective formation of bimetallic group 10 complexes using the Cs symmetric, bicyclic diphosphane P2C12H20 is reported herein. With its eclipsed lone pairs disposed at a relative angle of ca. 45 , the diphosphane framework is ideally suited to form multiple bridges between two metal centers. The complexes contain {M2P6} cages with three diphosphane bridges and a pair of trans-axial ligands such as EPh3 (E 1⁄4 P, As, Sb) or h1-P2C12H20. X-Ray crystallography experiments revealed that the cages have a pseudo-D3h symmetry, with metal–metal distances in the 3.9–4.1 A range. The complexes were isolated in 48–91% yield as crystalline, bright yellow or orange powders. Substitution of the axial ligands with the {M2P6} cages remaining intact was also observed.