2-Nitro-N'-[1-(pyridin-2-yl)ethyl-idene]benzohydrazide
Xiaofeng Li1, Yan An, Yiqing Chen
1Institute of Marine Materials Science and Engineering, Shanghai Maritime University, Shanghai 201306, People's Republic of China.
Acta Crystallographica. Section E, Structure Reports Online
|December 27, 2011
Summary
This study details the molecular structure of a novel organic compound, C(14)H(12)N(4)O(3). Researchers identified a significant twist between its aromatic rings, crucial for understanding its chemical properties and potential applications.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is fundamental to predicting their chemical behavior.
- Aromatic compounds, featuring delocalized pi electrons, exhibit unique reactivity and structural properties.
- Hydrogen bonding plays a critical role in the self-assembly and stability of molecular crystals.
Purpose of the Study:
- To elucidate the precise molecular geometry of the title compound, C(14)H(12)N(4)O(3).
- To quantify the dihedral and torsion angles defining the spatial relationship between the benzene and pyridine rings.
- To investigate the intermolecular interactions, specifically hydrogen bonding, within the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the atomic coordinates and bond parameters.
- Geometric analyses were performed to calculate dihedral and torsion angles.
- Analysis of intermolecular contacts identified hydrogen bonding patterns and quantified their geometry.
Main Results:
- The dihedral angle between the benzene and pyridine rings was determined to be 60.9 (2) .
- A significant torsion angle of 63.97 (12) was observed around the (NH)-(CO)-C(ar)-C(ar) bond, indicating a major twist in the molecule.
- Inversion dimers, formed by pairs of N-H ⋯ O hydrogen bonds, were identified, creating characteristic R (2) (8) loops in the crystal structure.
Conclusions:
- The title compound exhibits a pronounced non-planar conformation due to the twist between its aromatic systems.
- The identified hydrogen bonding network dictates the packing arrangement in the solid state, forming specific supramolecular motifs.
- These structural insights are vital for understanding the compound's physical properties and for designing related molecules with tailored characteristics.
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