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09:54
Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
4-Cyano-anilinium iodide
Acta Crystallographica. Section E, Structure Reports Online
|September 13, 2012
Summary
This study details the crystal structure of a compound, revealing disordered cation orientations. The arrangement involves specific layers of iodide ions and ammonium groups within the crystal lattice.
Area of Science:
- Crystallography
- Solid-state chemistry
Background:
- Understanding molecular arrangements in crystals is crucial for predicting material properties.
- Cation disorder can significantly influence crystal packing and intermolecular interactions.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(7)H(7)N(2) (+)·I(-).
- To analyze the nature and extent of cation disorder within the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the three-dimensional structure.
- Symmetry analysis was used to describe the cation's position and orientational disorder.
Main Results:
- The cation, C(7)H(7)N(2) (+), occupies a crystallographic site with 4mm symmetry, leading to significant disorder.
- Two distinct orientations of the six-membered ring and four rotational orientations of the ammonium group were identified.
- A layered structure was observed, with iodide ions and ammonium moieties forming layers perpendicular to the c-axis.
Conclusions:
- The crystal structure is characterized by extensive cation disorder due to symmetry constraints.
- The observed layered arrangement dictates the spatial distribution of ions and molecular fragments within the unit cell.
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