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Updated: Jun 24, 2025
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Crystallographic and spectroscopic studies on persistent triarylpropargyl cations
Takuya Shimajiri1,2, Taiga Tsue1, Shumpei Koakutsu1
1Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan. tak@sci.hokudai.ac.jp.
Stable, planar diarylmethyl cations with mesitylethynyl substituents were synthesized. These cations form charge-segregated crystal assemblies, leading to a red-shift in absorption due to intermolecular interactions.
Area of Science:
- Organic Chemistry
- Crystallography
- Photophysics
Background:
- Diarylmethyl cations are important intermediates in organic synthesis.
- Understanding the solid-state properties of organic cations is crucial for materials science.
Purpose of the Study:
- To synthesize and characterize novel mesitylethynyl-substituted diarylmethyl cations.
- To investigate the crystal packing and photophysical properties of these cations and their ion pairs.
Main Methods:
- Acid treatment of precursor alcohols to generate the cations.
- X-ray structural analysis to determine solid-state geometry and packing.
- UV-Vis absorption spectroscopy to study optical properties in the crystal.
Main Results:
- Stable, planar mesitylethynyl-substituted diarylmethyl cations were successfully isolated as solids.
- X-ray crystallography revealed charge-segregated assemblies in the crystal structure.
- Effective intermolecular interactions within the crystal induced a red-shift in the absorption spectrum.
Conclusions:
- Mesitylethynyl-substituted diarylmethyl cations exhibit unique planar geometries and form ordered supramolecular structures in the solid state.
- The observed red-shift in absorption is attributed to intermolecular interactions within the charge-segregated assemblies.
- These findings contribute to the understanding of structure-property relationships in organic ionic materials.
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