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Updated: May 13, 2026
19:58
Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
1-Methyl-4-(4-methylstyryl)pyridinium 4-methylbenzenesulfonate
M Krishnakumar1, S Sudhahar, A Silambarasan
1Department of Physics, Presidency College, Chennai 600 005, India.
Summary
This study details the crystal structure of a pyridine-benzene salt, revealing a near-planar cation due to a small dihedral angle. Intermolecular interactions like hydrogen bonds and pi-pi stacking stabilize the crystal lattice.
Area of Science:
- Crystallography
- Supramolecular Chemistry
Background:
- Understanding the packing of organic salts is crucial for predicting their physical properties.
- Non-classical hydrogen bonds and pi-pi interactions are key non-covalent forces influencing crystal structures.
Purpose of the Study:
- To characterize the crystal structure of the title salt.
- To investigate the intermolecular interactions governing crystal packing.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, bond angles, and intermolecular distances was performed.
Main Results:
- The crystal structure of the title salt (C15H16N(+)·C7H7O3S(-)) was determined.
- A small dihedral angle of 5.98° was observed between the pyridine and benzene rings of the cation.
- Weak C-H⋯O hydrogen bonds and π-π interactions were identified as stabilizing forces in the crystal lattice, with a centroid-centroid distance of 3.749 Å.
Conclusions:
- The cation exhibits a nearly planar conformation.
- The crystal packing is stabilized by a combination of hydrogen bonding and π-π interactions.
- This structural information provides insights into the solid-state behavior of this organic salt.
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