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 PdI2 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.