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Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
Building blocks for coordination polymers: self-assembled cleft-like and planar discrete metallo-macrocyclic
Maisara Abdul-Kadir1, Lyall R Hanton, Christopher J Sumby
1School of Chemistry & Physics, The University of Adelaide, Adelaide, SA 5005, Australia.
Dalton Transactions (Cambridge, England : 2003)
|February 23, 2012
Summary
New dinuclear metallo-macrocyclic complexes were synthesized using flexible and rigid amide ligands. The flexible ligand yielded cleft-shaped complexes, while the rigid ligand formed planar structures, suggesting potential as coordination polymer building blocks.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Discrete dinuclear metallo-macrocyclic complexes are of interest for their structural diversity and potential applications.
- Ligand design plays a crucial role in dictating the final complex architecture and properties.
Purpose of the Study:
- To synthesize and characterize novel dinuclear copper(II) metallo-macrocyclic complexes.
- To investigate the influence of ligand flexibility on the resulting complex structures.
- To explore the potential of these complexes as building blocks for coordination polymers.
Main Methods:
- Synthesis of two amide ligands: N-6-[(3-pyridylmethylamino)carbonyl]pyridine-2-carboxylic acid (L1-CH(3)) and its rigid analogue, N-6-[(3-pyridylamino)carbonyl]pyridine-2-carboxylic acid (L3-CH(3)).
- Preparation of dinuclear copper(II) complexes using these ligands with various counterions (NO3, Cl, ClO4) and solvent molecules (H2O, CH3OH).
- Structural characterization of the resulting complexes, including analysis of solid-state packing modes.
Main Results:
- Successful synthesis of discrete dinuclear metallo-macrocyclic complexes with general formulas [Cu(2)(L1-CH(3))(2)(X)(2)(Y)(2)] and [Cu(2)(L3-CH(3))(2)(X)(2)(Y)(2)].
- Complexes derived from the flexible ligand L1-CH(3) exhibited cleft-shaped structures, capable of conformational changes.
- Complexes derived from the rigid ligand L3-CH(3) adopted near-planar macrocyclic structures.
Conclusions:
- Ligand flexibility is a key determinant in the formation of cleft-shaped versus planar metallo-macrocyclic structures.
- The synthesized metallo-macrocyclic complexes demonstrate potential as versatile building blocks for constructing coordination polymers.
- This study highlights the importance of ligand design in controlling the supramolecular architecture of metal complexes.
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