Cofacial Organic Click Cage to Intercalate Polycyclic Aromatic Hydrocarbons

Area of Science:

• Supramolecular Chemistry
• Organic Synthesis
• Materials Science

Background:

• Polycyclic Aromatic Hydrocarbons (PAHs) are prevalent environmental pollutants with carcinogenic properties.
• Developing efficient methods for capturing and removing PAHs is crucial for environmental remediation and human health.
• Organic cages offer potential as tailored hosts for molecular recognition and sequestration.

Purpose of the Study:

• To synthesize a novel 3-fold symmetric cofacial organic cage (COC).
• To investigate the COC's capability to act as a receptor for carcinogenic PAHs.
• To elucidate the binding interactions and quantify the binding affinity of the COC towards PAHs.

Main Methods:

• Synthesis of the organic cage via Cu(I)-catalyzed azide-alkyne cycloaddition.
• Host-guest complexation studies with various carcinogenic PAHs.
• Spectroscopic techniques and X-ray diffraction analysis to confirm intercalation and binding modes.

Main Results:

• Successful synthesis of a 3-fold symmetric cofacial organic cage.
• Demonstrated efficient intercalation of carcinogenic PAHs within the COC's cavity.
• Quantified strong association constants (Ka) ranging from 3.7 × 10(4) to 1.3 × 10(6) M⁻¹.
• X-ray diffraction confirmed PAH intercalation within the COC structure.

Conclusions:

• The synthesized COC is an effective receptor for carcinogenic PAHs.
• Donor-acceptor and π···π stacking interactions facilitate PAH intercalation.
• The COC shows promise for applications in environmental remediation and pollutant sequestration.