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Heteroleptic metallosupramolecular racks, rectangles, and trigonal prisms: stoichiometry-controlled reversible
Subhadip Neogi1, Yvonne Lorenz, Marianne Engeser
1Center of Micro and Nanochemistry and Engineering, Organische Chemie I, Universität Siegen, Adolf-Reichwein-Strasse 2, D-57068 Siegen, Germany. neogi@chemie.uni-siegen.de
Inorganic Chemistry
|June 7, 2013
Summary
Researchers developed a simple method to create 2D rectangles and 3D prisms using metal complexes. The self-assembled structures can dynamically interconvert between different architectures based on component ratios.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Coordination Chemistry
Background:
- Self-assembly is a key strategy for constructing complex molecular architectures.
- Designing predictable and controllable self-assembly processes remains a challenge.
- Heteroleptic metal complexes offer tunable properties for advanced materials.
Purpose of the Study:
- To develop a straightforward method for preparing heteroleptic two-dimensional (2D) rectangles and three-dimensional (3D) triangular prisms.
- To explore the self-assembly of metal-loaded bisphenanthrolines with (multi)pyridine ligands.
- To investigate the dynamic behavior and interconversion of the resulting supramolecular architectures.
Main Methods:
- Utilizing the HETPYP (HETeroleptic PYridyl and Phenanthroline metal complexes) concept for self-assembly.
- Mixing metal-loaded linear bisphenanthrolines with diverse (multi)pyridine ligands.
- Characterization using NMR (1H, DOSY), ESI-FT-ICR mass spectrometry, Job plots, UV-vis titrations, DFT computations, and dynamic light scattering.
Main Results:
- Successfully prepared six different self-assembled architectures (2D rectangles, 3D prisms) spontaneously and without a template.
- Demonstrated stoichiometry-controlled interconversion between rectangular and rack architectures.
- Confirmed the dynamic nature of the assemblies through variable temperature NMR, DOSY NMR, and dynamic light scattering.
Conclusions:
- The HETPYP concept provides a simple and effective route to diverse heteroleptic supramolecular structures.
- The observed supramolecule-to-supramolecule interconversion highlights the dynamic nature of these assemblies.
- These dynamic constitutional systems offer potential for developing novel responsive materials.
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