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Updated: May 31, 2026
09:45
Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
Redetermination of (E)-N,N'-bis-(4-bromo-phen-yl)formamidine
1Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China.
Summary
This study provides a more accurate crystal structure of C(13)H(10)Br(2)N(2) than previous work. It details molecular arrangements, including hydrogen bonds and bromine interactions, enhancing our understanding of its solid-state structure.
Area of Science:
- Crystallography
- Solid-state chemistry
- Organic chemistry
Background:
- Previous structural studies of C(13)H(10)Br(2)N(2) reported limited atomic coordinate data.
- A need existed for a more precise structural determination including anisotropic displacement parameters and all hydrogen atom coordinates.
Purpose of the Study:
- To perform a high-accuracy redetermination of the crystal structure of C(13)H(10)Br(2)N(2).
- To elucidate the detailed molecular and crystal packing, including intermolecular interactions and hydrogen bonding.
Main Methods:
- Single-crystal X-ray diffraction.
- Analysis of crystallographic data to determine atomic coordinates, anisotropic displacement parameters, and geometric parameters.
- Identification of intermolecular interactions such as hydrogen bonds and halogen bonds.
Main Results:
- The crystal structure of C(13)H(10)Br(2)N(2) was determined with higher accuracy, including anisotropic displacement parameters for non-hydrogen atoms and coordinates for all hydrogen atoms.
- Two independent half-molecules occupy the asymmetric unit, related by a twofold rotation axis.
- Intermolecular N-H⋯N hydrogen bonds form dimers, and Br⋯Br interactions (3.4328 Å) create linear chains parallel to [102].
- Dihedral angles between benzene rings are 50.05° and 75.61° in the independent molecules.
- Hydrogen atoms on nitrogen are disordered over two positions due to molecular symmetry.
Conclusions:
- The redetermined structure provides a comprehensive and accurate description of C(13)H(10)Br(2)N(2) in the solid state.
- The study highlights the role of hydrogen bonding and halogen interactions in organizing the crystal lattice.
- This detailed structural information is crucial for understanding the compound's physical and chemical properties.
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