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Structural and Magnetic Properties of Dimeric Capsule Assemblies Formed by Cyclic Trinuclear Complexes
Masahiro Muto1, Kousuke Morinaga1, Momoko Nishihashi1
1Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Honjo 1, Saga 840-8502, Japan.
Molecules (Basel, Switzerland)
|September 28, 2024
Summary
Novel cyclic trinuclear iron and manganese complexes were synthesized. Complex 1 forms a unique dimeric capsule, while all complexes exhibit weak antiferromagnetic interactions between metal ions.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Asymmetric ditopic ligands offer versatile platforms for constructing complex metal architectures.
- Cyclic trinuclear complexes are of interest for their unique structural and magnetic properties.
Purpose of the Study:
- To synthesize and characterize novel cyclic trinuclear homo- and hetero-metal complexes.
- To investigate the structural diversity and supramolecular assembly of these complexes.
- To explore the magnetic interactions within the synthesized metal clusters.
Main Methods:
- Synthesis of asymmetric ditopic ligands: H3L3+2H and H3L3+2Br.
- Preparation and structural characterization of cyclic trinuclear complexes [{Fe(L3+2Br)py}3] (1), [{Mn(L3+2Br)}3(py)2 MeOH] (2), and [FeMn2(L3+2H)3(DMF)3] (3).
- Single-crystal X-ray diffraction for structural analysis.
- Magnetic susceptibility measurements to determine metal-metal interactions.
Main Results:
- Successful synthesis of three cyclic trinuclear complexes (1-3) using novel ligands.
- Complex 1 exhibits a unique tripod structure with three-fold symmetry, forming a dimeric capsule (approx. 3 × 1.6 × 1.6 nm³).
- Complexes 2 and 3 lack three-fold symmetry and do not form capsules.
- Magnetic studies revealed significantly weak antiferromagnetic interactions between metal ions in all complexes.
Conclusions:
- The asymmetric ditopic ligands enable the formation of diverse cyclic trinuclear metal complexes.
- Complex 1 demonstrates a rare dimeric capsule formation driven by its specific structure.
- The synthesized complexes exhibit weak antiferromagnetic coupling, providing insights into metal-metal interactions in such clusters.
Keywords:
X-ray structuresdimeric capsuleditopic ligandiron(III)magnetic susceptibilitymanganese(III)trinuclear complexMore Related Videos
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