Hollow and Solid Spheres Assembled from Functionalized Macrocycles Containing Adamantane

Area of Science:

• Supramolecular Chemistry
• Organic Synthesis
• Materials Science

Background:

• Adamantane derivatives are known for their unique cage structures and potential in materials science.
• Macrocyclic compounds offer diverse applications due to their tunable cavity sizes and host-guest properties.
• Self-assembly of molecular building blocks is crucial for creating complex supramolecular architectures.

Purpose of the Study:

• To synthesize novel adamantane-based macrocycles with varying functional groups.
• To investigate the self-assembly behavior and structural characteristics of these macrocycles.
• To explore the influence of substituents and solvent effects on the formation of supramolecular structures.

Main Methods:

• Multi-step organic synthesis for adamantane-based macrocycle preparation.
• X-ray crystallography for detailed structural analysis of the macrocyclic framework.
• Solution-phase studies to observe self-assembly phenomena under different solvent conditions.

Main Results:

• Synthesis of an eight-hydroxyl adamantane macrocycle (1) and its functionalized derivatives (2, 3).
• X-ray analysis revealed a hexagonal macrocyclic backbone with a central cavity, capable of forming tubular structures.
• Macrocycle (1) formed hollow spherical aggregates in acetone, while macrocycle (3) self-assembled into spheres and fused networks in a chloroform/hexane mixture.

Conclusions:

• Adamantane-based macrocycles exhibit tunable self-assembly properties based on their functional groups.
• The solvent environment plays a critical role in directing the formation of supramolecular structures, from hollow spheres to crystalline networks.
• These findings open avenues for designing novel self-assembling materials with controlled architectures.