Accessing the inaccessible: discrete multinuclear coordination complexes and selective anion binding attainable only
Basil M Ahmed1, Gellert Mezei1
1Department of Chemistry, Western Michigan University, Kalamazoo, Michigan, USA. gellert.mezei@wmich.edu.
Chemical Communications (Cambridge, England)
|December 9, 2016
Summary
Novel copper complexes were synthesized using tethered pyrazole ligands, leading to nanojars with selective ion binding. These nanojars exclusively capture carbonate ions, avoiding sulfate ions.
Area of Science:
- Coordination chemistry
- Supramolecular chemistry
- Materials science
Background:
- Pyrazole ligands are common in coordination chemistry but can lead to undesired structures.
- Synthesizing specific multimetallic complexes can be challenging due to competing reaction pathways.
Purpose of the Study:
- To develop a novel method for synthesizing multimetallic copper pyrazolate complexes.
- To investigate the ion-binding properties of nanojars constructed with tethered pyrazole ligands.
Main Methods:
- Synthesis of pyrazole ligands locked with ethylene tethers.
- Formation of multimetallic copper pyrazolate complexes.
- Fabrication of nanojars using the tethered ligand.
- Testing the selectivity of nanojars for carbonate and sulfate ions.
Main Results:
- Novel multimetallic copper pyrazolate complexes were successfully synthesized using ethylene-tethered pyrazole ligands.
- Nanojars incorporating these tethered ligands exhibited complete selectivity for carbonate ions over sulfate ions.
- The ethylene tether effectively directed the formation of the desired pyrazolate structures, overcoming competing motifs.
Conclusions:
- Tethering pyrazole ligands is an effective strategy to access specific multimetallic copper pyrazolate architectures.
- The resulting nanojars demonstrate remarkable and selective ion-binding capabilities, particularly for carbonate ions.
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