Redox-active, multinuclear (ferrocenylethynyl) phosphanes and their palladium and platinum complexes

A series of (ferrocenylethynyl) phosphanes with increasing number of ferrocenylethynyl units, including corresponding PdCl2, PtCl2, and Pdl(2) complexes were prepared, their spectroscopic data investigated, and the solid-state structures of three of the complexes determined. The complexes exhibit increased steric bulk, affording bent ethynyl moieties in the cis-configured PdCl2 and PtCl2 complex. The PdI2=based complex shows a favorable trans-configuration with almost linear acetylene units. The thermal behavior of some of the complexes indicated their utility as potential precursors for magnetic ceramic nanomaterials. Electrochemical investigations of the ligands and the corresponding complexes revealed that the structural motif of the ligands does not support multistep redox processes within the materials. All compounds showed single, reversible redox processes whose potential is influenced by the substitution pattern of the ligands as well as the respective complex geometries.