Binaphthyl-Based Macrocycles as Optical Sensors for Aromatic Diphenols

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Stereochemistry

Background:

• Development of novel molecular architectures with defined symmetries is crucial for advanced applications.
• Homochiral macrocycles offer unique properties for molecular recognition and catalysis.
• 1,1'-binaphthyl-2,2'-diol (BINOL) is a versatile chiral scaffold for constructing complex molecules.

Purpose of the Study:

• To synthesize novel rigid, homochiral organic macrocycles with D2 and D3 symmetries.
• To investigate the structural and conformational variability of these macrocyclic scaffolds.
• To explore the complexation behavior of the synthesized macrocycles with aromatic diphenols.

Main Methods:

• One-pot esterification reactions using aromatic dicarboxylic acids and BINOL-derived dibenzylic alcohols.
• Nuclear Magnetic Resonance (NMR) spectroscopy for structural elucidation and monitoring chemical shifts.
• Circular Dichroism (CD) spectroscopy to analyze conformational changes and chirality.

Main Results:

• Successful synthesis of rigid, homochiral macrocycles with D2 and D3 symmetries in good yields.
• NMR and CD spectroscopy confirmed structural diversity and shape variability within the macrocyclic frameworks.
• D2-symmetric macrocycles demonstrated stable complex formation with aromatic diphenols, sensitive to cavity size.

Conclusions:

• The study presents a facile route to structurally diverse, homochiral macrocycles.
• The synthesized macrocycles exhibit tunable recognition properties based on their internal cavity dimensions.
• These findings open avenues for designing tailored host molecules for specific guest binding applications.