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Published on: January 19, 2016
(4-Meth-oxy-phen-yl)methanaminium chloride
Acta Crystallographica. Section E, Structure Reports Online
|April 28, 2011
Summary
The crystal structure of a methoxy-phenyl-methyl-ammonium chloride salt reveals a unique open framework. Hydrogen bonds between cations and anions create layered structures with alternating hydrophobic and hydrophilic regions.
Area of Science:
- Crystallography
- Materials Science
- Supramolecular Chemistry
Background:
- Understanding the crystal packing and intermolecular interactions of organic salts is crucial for designing new materials.
- The (4-methoxyphenyl)methanaminium cation offers a combination of aromatic and polar functionalities for hydrogen bonding.
- Chloride anions are common counterions that can participate in various hydrogen bonding networks.
Purpose of the Study:
- To determine the detailed crystal structure of the (4-methoxyphenyl)methanaminium chloride salt.
- To investigate the hydrogen bonding patterns and their influence on the overall crystal architecture.
- To characterize the resulting framework and identify distinct hydrophobic and hydrophilic regions.
Main Methods:
- Single-crystal X-ray diffraction was employed to elucidate the three-dimensional crystal structure.
- Analysis of bond lengths, angles, and intermolecular distances to identify hydrogen bonding interactions (N-H⋯Cl and C-H⋯O).
- Calculation of root-mean-square (r.m.s.) deviations from planes to assess the planarity of the methoxy and phenylene groups.
Main Results:
- The crystal structure of (4-methoxyphenyl)methanaminium chloride was successfully determined.
- The methoxy group was found to be co-planar with the phenylene ring (r.m.s. deviation of 0.005 Å).
- An open framework architecture was observed, driven by N-H⋯Cl and C-H⋯O hydrogen bonds, forming layered structures.
Conclusions:
- The crystal packing is dominated by hydrogen bonding interactions between the ammonium cations and chloride anions.
- The arrangement of these bonds leads to the formation of alternating hydrophilic (containing ammonium and chloride) and hydrophobic (containing anisole groups) layers.
- This study provides insights into the supramolecular assembly of organic salts and the formation of porous frameworks.
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