Metal-Templated Oligomeric Macrocyclization via Coupling for Metal-Doped π-Systems

Area of Science:

• Coordination Chemistry
• Organic Synthesis
• Materials Science

Background:

• Aromatic macrocycles are crucial in supramolecular chemistry and materials science.
• Developing efficient synthetic routes for complex macrocyclic structures remains a challenge.
• Metal-templated synthesis offers a powerful strategy for constructing macrocycles with specific architectures.

Purpose of the Study:

• To develop a novel method for synthesizing metal-doped aromatic macrocycles.
• To explore the utility of nickel as a template for macrocyclization.
• To create large π-conjugated molecules with potential applications in advanced materials.

Main Methods:

• Metal-templated oligomeric macrocyclization via coupling using nickel (Ni).
• Assembly of five pyridine units through Ni-mediated coupling to form aryl-aryl linkages.
• Gram-scale synthesis of the pentameric oligopyridyl macrocycle.

Main Results:

• Selective synthesis of a pentameric oligopyridyl macrocycle in good yield.
• Formation of a paramagnetic pentagonal-bipyramidal complex by capturing Ni(II) at the macrocycle's center.
• Successful synthesis of a nanometer-sized, bowl-shaped molecule with 120π and 8d electrons.

Conclusions:

• The developed Ni-templated method is efficient for synthesizing aromatic macrocycles.
• This approach enables the construction of large π-molecules with unique electronic and structural features.
• The synthesized macrocycles hold promise for applications in areas requiring advanced π-systems.