A Valence Tautomeric Dinuclear Copper Tetrakisguanidine Complex
Sven Wiesner1, Arne Wagner1, Elisabeth Kaifer1
1Anorganisch-Chemisches Institut, Ruprecht-Karls Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|June 17, 2016
Summary
This study introduces the first valence tautomeric dinuclear copper complex with a redox-active guanidino-functionalized aromatic ligand. Its electronic structure and catalytic potential are tunable by solvent and temperature.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Catalysis
Background:
- Valence tautomerism in transition metal complexes offers tunable electronic properties.
- Guanidino-functionalized aromatic (GFA) ligands can act as redox-active components.
- Dinuclear copper complexes are relevant in various catalytic processes.
Purpose of the Study:
- To synthesize and characterize the first valence tautomeric dinuclear copper complex.
- To investigate the influence of the environment on the complex's electronic structure.
- To explore the potential of this system in catalysis.
Main Methods:
- Synthesis of a novel dinuclear copper complex with a GFA ligand.
- Spectroscopic and crystallographic analysis in different solvents and temperatures.
- Electrochemical studies to probe redox behavior.
Main Results:
- The complex exhibits valence tautomerism, switching between Cu(II)/neutral GFA and Cu(I)/oxidized GFA forms.
- The electronic structure is highly dependent on the solvent polarity and temperature.
- A temperature-dependent equilibrium was observed in acetone, demonstrating accessibility of both forms.
Conclusions:
- The developed GFA ligand enables valence tautomerism in dinuclear copper complexes.
- Environmental factors like solvent and temperature are critical for controlling the electronic state.
- This work expands the utility of valence tautomeric complexes in catalysis by tolerating anionic coligands.
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