Readily functionalized AAA-DDD triply hydrogen-bonded motifs.

Area of Science:

• Supramolecular Chemistry
• Organic Synthesis
• Polymer Science

Background:

• Hydrogen bonding is crucial for self-assembly in supramolecular chemistry.
• Designing specific hydrogen bond motifs is key to controlling material properties.
• Existing motifs may lack versatility or ease of functionalization.

Purpose of the Study:

• To synthesize and characterize a novel AAA-DDD hydrogen bond array.
• To investigate the complexation behavior of the new motif.
• To demonstrate its application in supramolecular polymerization.

Main Methods:

• Two-step synthesis of AAA monomeric units (3a-b) from 2-aminonicotinaldehyde using microwave radiation.
• Characterization using 1H NMR and fluorescence spectroscopy to determine association constants.
• Viscosity measurements to assess supramolecular polymerization in a crosslinked copolymer.

Main Results:

• Successful synthesis of AAA monomeric units with 52-66% yield.
• Confirmed strong complexation with an association constant of 1.57 × 107 M-1.
• Demonstrated utility in supramolecular polymerization via viscosity studies.

Conclusions:

• A readily functionalizable AAA-DDD hydrogen bond array was successfully developed.
• The motif exhibits robust binding, suitable for supramolecular assembly.
• This work provides a new building block for designing advanced supramolecular polymers.