Synthesis of macrocyclic salen rare-earth complexes and their framework conversion regulated by coordination sphere...

Area of Science:

• Inorganic Chemistry
• Supramolecular Chemistry
• Materials Science

Background:

• Rare-earth elements exhibit flexible coordination numbers, enabling complex structural arrangements.
• Self-assembly in coordination chemistry is crucial for designing novel materials.
• Controlling the assembly of metal complexes is a key challenge in inorganic chemistry.

Purpose of the Study:

• To report a novel macrocyclic rare-earth complex.
• To demonstrate the regulation of complex frameworks between trimer and tetramer states.
• To explore the use of external capping ligands for structural control.

Main Methods:

• Synthesis of a macrocyclic rare-earth complex.
• Utilizing an external capping ligand to influence self-assembly.
• Characterization of the resulting supramolecular structures.

Main Results:

• A macrocyclic rare-earth complex was successfully synthesized.
• The complex framework could be reversibly regulated between trimer and tetramer structures.
• The external capping ligand was identified as the key regulator.

Conclusions:

• Coordination sphere engineering of rare-earth metals provides a method for controlling self-assembled structures.
• Flexible coordination numbers (CN > 6) are essential for this structural regulation.
• This work offers a new strategy for designing tunable supramolecular architectures.