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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Thermally stable intermolecular proton bonds in polyaromatic aldehyde crystals
Sung Woo Heo1, In-Chul Hwang, Young Chun
1Department of Chemistry, Pohang University of Science and Technology, Pohang 790-784, Korea.
Chemistry, an Asian Journal
|June 1, 2011
Summary
Researchers synthesized red-colored proton complexes from polyaromatic aldehyde derivatives using strong hydrogen bonding. These stable, hydrophobic compounds feature Zundel-like cationic hydrogen bonds, confirmed by X-ray and IR spectroscopy.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Organic Chemistry
Background:
- Polyaromatic hydrocarbons (PAHs) are versatile building blocks in materials science.
- Hydrogen bonding plays a crucial role in the self-assembly and properties of molecular materials.
- Developing novel proton complexes with enhanced stability is of significant interest.
Purpose of the Study:
- To synthesize and characterize novel red-colored proton complexes of polyaromatic aldehydes.
- To investigate the role of intermolecular hydrogen bonding in the formation and stability of these complexes.
- To explore the structural and spectral properties of the resulting proton complexes.
Main Methods:
- Synthesis of polyaromatic aldehyde derivatives, specifically 1-pyrenecarbaldehyde (Py-CHO).
- Reaction of Py-CHO with tetrachloroauric acid (HAuCl4) under dry conditions to form proton complexes.
- Confirmation of complex formation using single-crystal X-ray diffraction and infrared (IR) spectroscopy at various temperatures.
Main Results:
- Successful synthesis of red-colored proton complexes, specifically [(Py-CHO)2H][AuCl4].
- X-ray analysis and IR spectroscopy confirmed the presence of strong intermolecular hydrogen bonding, forming Zundel-like cationic hydrogen bonds (O-H(+)-O) with short O-O distances (≈2.4 Å).
- The complexes exhibited hydrophobic properties, limited solubility in polar organic solvents, and thermal stability up to 100 °C due to layered structures with π-π interactions.
Conclusions:
- The study successfully synthesized and characterized novel proton complexes of polyaromatic aldehydes stabilized by strong intermolecular hydrogen bonds.
- The Zundel-like cationic hydrogen bonds and π-π stacking interactions contribute to the observed thermal stability and structural integrity.
- These findings offer insights into the design of self-assembled supramolecular materials with tunable properties.
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