Dipalladium Complexes with Bridging Monoalkyl or Monophenyl Silyl Ligands in the Solid State and in Solution

HexSiH3, PhSiH3, and PhSiClH2 reacted with [Pd(PCy3)2] to yield dipalladium complexes with bridging silyl ligands: [{Pd(PCy3)}2(μ-HSiXR)2] (1, R = Hex, X = H; 2, R = Ph, X = H; 3, R = Ph, X = Cl). The X-ray crystallographic results displayed a typical bis(silyl)-bridged dinuclear structure with an anti conformation of the substituents on the Si atom in the solid state. Temperature-dependent NMR spectroscopic analyses of 1 and 2 revealed a dynamic syn–anti isomerization of the complex via exchange of the bridging and nonbridging Si–H hydrogens in solution. Complex 3 with bridging chloro(phenyl)silyl ligands did not show such a dynamic behavior.