Modulating the Dimensions of Rectangular Hydrazone-Based Bispyridinium Macrocyclic Receptors.

Area of Science:

• Supramolecular Chemistry
• Organic Chemistry
• Materials Science

Background:

• Macrocyclic molecular receptors are crucial for supramolecular chemistry advancements.
• Challenges remain in synthesis, aqueous performance, and stimuli-responsiveness of host-guest systems.

Purpose of the Study:

• To develop a new family of self-assembled polycationic molecular rectangles.
• To investigate their synthesis, aqueous performance, and molecular recognition properties.
• To explore their potential as pH-responsive macrocyclic receptors.

Main Methods:

• Modular synthesis via acid-catalyzed imine condensation in water.
• Gram-scale synthesis achieving acceptable yields.
• NMR spectroscopy to study aqueous molecular recognition with a model guest.

Main Results:

• Successfully synthesized a new family of polycationic molecular rectangles with tunable dimensions.
• Demonstrated efficient synthesis in water on a gram scale.
• Observed formation of highly stable binary and ternary inclusion complexes in aqueous media.

Conclusions:

• The new macrocyclic receptors exhibit tunable binding properties and excellent aqueous performance.
• These pH-responsive receptors show significant potential for applications in host-guest chemistry.
• The modular synthesis approach offers a highly efficient route to these novel compounds.