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Acid-base-driven interconversion between a mononuclear complex and supramolecular coordination polymers in a
Aurélien Gasnier1, Jean-Michel Barbe, Christophe Bucher
1Département de Chimie Moléculaire, UMR CNRS 5250, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 9, France.
Inorganic Chemistry
|February 20, 2008
Summary
Researchers developed a novel ligand to create distinct copper complexes or metallopolymers. This acid-base system allows reversible switching between these structures by controlling copper ion location.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Polytopic ligands offer versatile coordination environments.
- Metal-ligand interactions are fundamental to supramolecular assembly.
- Controlling metallopolymer formation is key for advanced materials.
Purpose of the Study:
- To synthesize a polytopic cyclam-bis-terpyridine ligand.
- To investigate the acid-base-triggered self-assembly of copper complexes and metallopolymers.
- To achieve controlled interconversion between mononuclear and polymeric forms.
Main Methods:
- Synthesis of a novel polytopic cyclam-bis-terpyridine ligand.
- Coordination of Cu(2+) ions to the ligand.
- Acid-base titration to trigger complex formation and interconversion.
- Spectroscopic and structural characterization of the resulting species.
Main Results:
- Successful formation of a mononuclear neutral complex with Cu(2+).
- Formation of Cu(2+)-containing metallopolymers.
- Demonstration of acid-base-triggered reversible switching between the mononuclear and polymeric states.
- The interconversion is driven by the reversible displacement of Cu(2+) between macrocyclic and terpyridine binding sites.
Conclusions:
- The designed ligand enables facile control over copper coordination modes.
- Acid-base stimuli can reversibly modulate the assembly from discrete complexes to extended metallopolymers.
- This work provides a pathway for designing responsive metallo-supramolecular materials.
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