Click Chemistry Derived Pyridazines: Electron-Deficient Building Blocks with Defined Conformation and Packing...

Area of Science:

• Organic Chemistry
• Materials Science
• Supramolecular Chemistry

Background:

• Pyridazine derivatives are important scaffolds in medicinal and materials chemistry.
• Fluorinated organic molecules offer unique electronic and structural properties.
• Triazole linkages are versatile for constructing complex molecular architectures.

Purpose of the Study:

• To synthesize novel 3,6-bis(4-triazolyl)pyridazines with varying fluorination.
• To investigate the structure-property relationships of these compounds in different phases.
• To explore their potential applications in organic electronics.

Main Methods:

• Copper-catalyzed azide-alkyne cycloaddition for synthesis.
• Density Functional Theory (DFT) calculations for gas-phase structure.
• NMR spectroscopy for solution-state analysis.
• Single-crystal X-ray diffraction for solid-state structure determination.
• Electrochemistry and optical spectroscopy for electronic properties.

Main Results:

• Successful synthesis of a series of fluorinated 3,6-bis(4-triazolyl)pyridazines.
• Molecular structure is dominated by the anti-conformation of triazole-pyridazine linkages.
• Supramolecular assembly in the solid state is governed by π-stacking, C-H⋅⋅⋅π, and tunable C-F⋅⋅⋅H interactions.
• Fluorine substitution influences crystal packing, leading to herringbone, 1D, or 2D lamellar structures.

Conclusions:

• The synthesized compounds possess tunable solid-state structures driven by specific intermolecular interactions.
• The electronic and optical properties suggest suitability for organic electronic applications.
• These fluorinated triazolylpyridazines represent promising candidates for electron-transporting and hole-blocking layers.