Tetrapalladium complex with bridging germylene ligands. Structural change of the planar Pd4Ge3 core.

A complex with a planar hexagonal Pd(4)Ge(3) core, [Pd{Pd(dmpe)}(3)(μ(3)-GePh(2))(3)], was synthesized and characterized by X-ray and NMR measurements as well as by DFT calculations. 4-tert-Butylbenzenethiol converted the Pd(4) complex into a hexapalladium complex, [{Pd(3)(μ-GePh(2))(2)(μ-H)(μ(3)-GePh(2)(SC(6)H(4)(t)Bu-4))}(2)(μ-dmpe)], composed of two Pd(3)Ge(3) units bridged by a dmpe ligand. The addition of CuI or AgI to the Pd(4) complex yielded [Pd(μ-MI){Pd(dmpe)}(3)(μ(3)-GePh(2))(3) ] (M = Cu, Ag), in which Cu or Ag bridges a Pd-Pd bond of the Pd(4)Ge(3) core. The CuI adducts in solution undergo a pivot motion of the CuI on the surface of the Pd(4)Ge(3) plane on the NMR time scale.