Palladium Complexes of Carbazole-Based Chalcogenaisophlorins: Synthesis, Structure, and Solid-State NIR Absorption...

Area of Science:

• Organic Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Carbazole derivatives are important in organic electronics.
• Isophlorin frameworks offer unique electronic properties.
• Metallation can stabilize and tune molecular structures.

Purpose of the Study:

• To synthesize novel carbazole-based chalcogenaisophlorins.
• To create and characterize their palladium complexes.
• To investigate their photophysical properties and structural characteristics.

Main Methods:

• Annulation reactions for synthesis.
• Nuclear Magnetic Resonance (NMR) spectroscopy for structural elucidation.
• X-ray diffraction analysis for solid-state structure determination.
• Density Functional Theory (DFT) calculations for electronic properties.

Main Results:

• Successful synthesis of carbazole-based chalcogenaisophlorins (2-4) and their palladium complexes (2Pd-4Pd).
• Structural characterization confirmed metallation-induced stabilization and weak antiaromaticity.
• Weak near-infrared (NIR) absorption observed in solution, typical for antiaromatic porphyrinoids.
• Stronger solid-state NIR absorption for complexes 2Pd and 3Pd, attributed to intermolecular charge transfer in stacked structures.

Conclusions:

• Palladium complexes of carbazole-based chalcogenaisophlorins exhibit interesting photophysical properties.
• The 20π isophlorin framework contributes to weak antiaromatic character.
• Intermolecular interactions in solid-state structures significantly influence NIR absorption, indicating potential for optoelectronic applications.