(E)-1-Methyl-4-[2-(2-naphth-yl)vin-yl]pyridinium iodide
Summary
The crystal structure of a pyridinium-naphthalene compound reveals cation disorder and significant pi-pi interactions between aromatic rings. These interactions influence the packing and stability of the iodide salt in the solid state.
Area of Science:
- Crystallography
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Understanding the solid-state behavior of organic salts is crucial for materials science.
- Pyridinium and naphthalene moieties are common in functional organic materials.
- Cation disorder can significantly impact crystal packing and physical properties.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(18)H(16)N(+)·I(-).
- To investigate the nature of intermolecular interactions, including pi-pi stacking and hydrogen bonding.
- To analyze the effect of cation disorder on the overall crystal architecture.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, bond angles, and dihedral angles provided structural insights.
- Intermolecular interactions were identified and quantified using crystallographic data.
Main Results:
- The title compound crystallizes as an iodide salt with a disordered pyridinium-naphthalene cation.
- Two distinct orientations of the cation were observed due to 180° rotational disorder.
- Significant pi-pi interactions were found between the pyridinium and naphthalene systems, with a centroid-centroid distance of 3.442 Å.
- C-H···I interactions link the cations and iodide anions, while weak C-H···pi interactions involving the methyl group were also noted.
Conclusions:
- The crystal structure is characterized by stacked cations with substantial pi-pi overlap.
- Cation disorder and intermolecular interactions dictate the packing arrangement and stability of the iodide salt.
- The findings provide insights into the supramolecular assembly of organic salts containing pyridinium and naphthalene units.
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