An Organic Mixed-Valence Ligand for Multistate Redox-Active Coordination Networks.

The multistate redox-active/multi-interactive ligand 5,5',8,8'-tetra(4-pyridyl)-2,2'-(1,4-phenylene)bis-1H-perimidine (H ₂ TPP) was designed and synthesized. H ₂ TPP undergoes four one-electron oxidation steps, and was used for the preparation of a multistate redox-active coordination network in a solid-liquid interface reaction using molten Cd ²⁺ salts. The multiple redox states of H ₂ TPP were confirmed spectroscopically by stepwise four-electron oxidation. Spectroscopic analysis indicated that the mixed-valence states of the ligand are class II on the UV/Vis/NIR timescale and borderline class II/class III on the ESR timescale.
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