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A series of (ferrocenylethynyl)phosphanes with increasing number of ferrocenylethynyl units, including corresponding PdCl 2 , PtCl 2 , and PdI 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 PdCl 2 and PtCl 2 complex. The PdI 2based 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.

Catechol ligands that bear carbonyl functions such as esters or aldehydes in the 3-position (1a-c-H 2 ) form triple-stranded, helicate-type complexes [Li 3 (1a-c) 6 Ti 2 ] -with titanium(IV) and the corresponding double-stranded compounds [Li 2 (1a-c) 4 B 2 ] with boron(III) in hierarchical, lithium-templated processes. The related 8-hydroxyquinoline ligands 2a,b-H can be used for the formation of similar complexes

Based on chiral, enantiomerically pure 7-[(S)-phenylethylurea]-8-hydroxyquinoline (1-H), trinuclear helicate-type complexes 2-5 are formed with divalent transition-metal cations. X-ray structural analyses reveal the connection of two monomeric complex units [M(1)(3)](-) (M=Zn, Mn, Co, Ni) by a central metal ion to form a "dimer". Due to the enantiopurity of the ligand, the complexes are obtained as pure enantiomers, resulting in pronounced circular dichroism (CD) spectra. Single-ion effects and intra- and intermolecular coupling are observed with dominating ferromagnetic coupling in the case of the cobalt(II) and nickel(II) and dominating antiferromagnetic coupling in the case of the manganese(II) complex.