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08:43
Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
4-Cyano-anilinium bromide
David J Vumbaco1, Michael N Kammer, Lynn V Koplitz
1Department of Biological Sciences, Loyola University, New Orleans, LA 70118, USA.
Acta Crystallographica. Section E, Structure Reports Online
|November 6, 2012
Summary
The crystal structure reveals that cations form dimers and sheets through hydrogen bonds. These interactions involve C-H⋯N and C-H⋯Br bonds, influencing the compound's molecular arrangement.
Area of Science:
- Crystal engineering
- Supramolecular chemistry
- Organic chemistry
Background:
- Understanding intermolecular forces is crucial for crystal design.
- Hydrogen bonding plays a key role in molecular self-assembly.
- C-H⋯N and C-H⋯Br interactions are increasingly recognized as important non-covalent forces.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(7)H(7)N(2) (+)·Br(-).
- To investigate the role of hydrogen bonding in the self-assembly of the crystal lattice.
- To characterize the specific types and geometries of intermolecular interactions present.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional crystal structure.
- Analysis of hydrogen bonding networks, including C-H⋯N and C-H⋯Br interactions.
- Geometric analysis of the crystal packing, including distances and angles.
Main Results:
- The crystal structure features cations associated into inversion dimers via C-H⋯N hydrogen bonds.
- These dimers further assemble into stepped sheets, also mediated by C-H⋯N interactions.
- The spacing between aromatic rings in adjacent dimers was measured at 1.124(6) Å.
- N-H⋯Br and C-H⋯Br interactions link the sheets together, with three N-H⋯Br and two C-H⋯Br interactions per cation.
Conclusions:
- The crystal packing is governed by a combination of C-H⋯N and C-H⋯Br hydrogen bonding.
- The observed supramolecular architecture, including dimers and stepped sheets, arises from these specific interactions.
- This study provides insights into the role of weak hydrogen bonds in directing crystal structure formation.
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