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Updated: Jun 1, 2026
06:46
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
N'-[(E)-2,6-Dichloro-benzyl-idene]pyrazine-2-carbohydrazide
Summary
This study details the non-planar structure of a novel dichloro-pyrazine-amide compound. It reveals intricate intermolecular hydrogen bonding and C-H interactions that form stable supramolecular chains.
Area of Science:
- Crystallography and Molecular Structure
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is crucial for predicting their properties.
- Supramolecular chemistry explores the non-covalent interactions that govern the assembly of molecules into larger structures.
- Hydrogen bonding and other weak interactions play a significant role in crystal engineering and material design.
Purpose of the Study:
- To elucidate the crystal structure and intermolecular interactions of the title compound, C(12)H(8)Cl(2)N(4)O.
- To investigate the role of hydrogen bonding and C-H interactions in the self-assembly of the molecule into supramolecular architectures.
- To characterize the non-planar conformation and dihedral angles between the pyrazine and benzene rings.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the precise three-dimensional structure of the compound.
- Analysis of the crystal structure involved identifying and quantifying intra- and intermolecular hydrogen bonds (N-H⋯N, N-H⋯O).
- Geometric parameters, including dihedral angles and bond distances/angles, were analyzed to understand molecular conformation and packing.
Main Results:
- The title compound, C(12)H(8)Cl(2)N(4)O, exhibits a non-planar geometry with a dihedral angle of 12.55° between the pyrazine and benzene rings.
- An intramolecular N-H⋯N hydrogen bond was identified within the molecule.
- Amide groups self-associate through intermolecular N-H⋯O hydrogen bonding, forming supramolecular chains along the [101] direction, further stabilized by C-H⋯O and C-H⋯N interactions.
Conclusions:
- The crystal structure analysis reveals a unique non-planar conformation driven by intramolecular hydrogen bonding.
- The formation of robust supramolecular chains is primarily mediated by amide N-H⋯O hydrogen bonds, showcasing effective crystal engineering.
- The study highlights the interplay of various non-covalent interactions in dictating the solid-state architecture of organic molecules.
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