Multiple folding structures mediated by metal coordination of acyclic multidentate ligand

Area of Science:

• Coordination Chemistry
• Supramolecular Chemistry
• Materials Science

Background:

• Bis(N(2)O(2)) ligands offer versatile coordination sites for transition metals.
• Flexible linkers can influence the self-assembly and structural outcomes of metal complexes.
• Understanding metal-ligand interactions is key to designing novel supramolecular architectures.

Purpose of the Study:

• To investigate the structural diversity arising from metal complexation of a bis(N(2)O(2)) ligand with a flexible diethyleneoxy linker.
• To explore the role of different metal ions in dictating the folding modes of the resulting complexes.
• To understand the relationship between metal-ligand affinity and the observed supramolecular structures.

Main Methods:

• Synthesis of a bis(N(2)O(2)) ligand featuring a diethyleneoxy linker.
• Metal complexation reactions with various d-block transition metal ions and hard metal cations.
• Structural characterization of the resulting complexes using techniques such as X-ray crystallography.

Main Results:

• Formation of four distinct folded structures: meso double helical, folded Omega-shaped, S-shaped helical, and single helical.
• Demonstration that the specific metal ion combination dictates the folding mode.
• Observation of structural interconversion between folded forms driven by differences in metal cation affinity.

Conclusions:

• The flexible diethyleneoxy linker and N(2)O(2) coordination sites enable the formation of diverse supramolecular architectures.
• Metal ion selection is a critical factor in controlling the self-assembly and folding patterns of these bis(N(2)O(2)) complexes.
• The study highlights the potential for designing switchable supramolecular systems based on metal-ligand interactions.