Selective Construction of Pseudo-Mortise-and-Tenon-Type Molecules

Area of Science:

• Supramolecular Chemistry
• Coordination Chemistry

Background:

• Ring-in-ring complexes often lack stability due to weak intermolecular forces.
• Existing stabilization methods rely on van der Waals forces or hydrogen bonding alone.

Purpose of the Study:

• To develop a novel stabilization strategy for ring-in-ring complexes.
• To enhance the stability and explore new architectures of metallo-supramolecular assemblies.

Main Methods:

• Utilized the mortise-and-tenon principle for molecular design.
• Employed crystal structure analysis of Rh-1 assembly.
• Synthesized analogous iridium complex (Ir-1) using the same protocol.

Main Results:

• Achieved enhanced stability in ring-in-ring complexes via dense π-π stacking and van der Waals interactions.
• Successfully constructed molecular figure-eight knots (Rh-2, Ir-2) and metalla[2]catenanes (Rh-3, Ir-3).
• Demonstrated the versatility of the mortise-and-tenon platform for complex molecular architectures.

Conclusions:

• The mortise-and-tenon strategy significantly increases the dissociation energy barrier of ring-in-ring complexes.
• This principle provides a robust platform for designing complex supramolecular structures like knots and catenanes.