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5-Bromo-N-[(E)-(6-bromo-pyridin-2-yl)methyl-idene]pyridine-3,4-diamine
1Department of Chemistry, Tangshan Normal University, Tangshan 063000, People's Republic of China.
Acta Crystallographica. Section E, Structure Reports Online
|December 27, 2011
Summary
This study details a novel Schiff base, C(11)H(8)Br(2)N(4), synthesized from brominated pyridine precursors. Its molecular structure features an E configuration and is stabilized by intramolecular hydrogen bonding, with crystal packing forming chains.
Area of Science:
- Organic Chemistry
- Crystallography
- Supramolecular Chemistry
Background:
- Schiff bases are versatile organic compounds with diverse applications.
- Brominated pyridine derivatives are important building blocks in medicinal chemistry and materials science.
- Understanding molecular conformation and crystal packing is crucial for predicting material properties.
Purpose of the Study:
- To synthesize and characterize a novel Schiff base derived from brominated pyridine precursors.
- To elucidate the molecular structure, including bond configuration and dihedral angles.
- To investigate the intermolecular interactions and crystal packing of the synthesized compound.
Main Methods:
- Synthesis of the Schiff base via condensation reaction.
- Single-crystal X-ray diffraction analysis to determine molecular and crystal structure.
- Spectroscopic methods (e.g., NMR, IR) for compound characterization.
Main Results:
- The title compound, C(11)H(8)Br(2)N(4), was successfully synthesized.
- X-ray diffraction revealed an E configuration around the C=N bond and a dihedral angle of 14.02° between pyridine rings.
- An intramolecular N-H⋯N hydrogen bond stabilizes the molecular conformation.
- Crystal structure analysis showed molecules stacked along the b axis and linked into chains via N-H⋯N hydrogen bonds along the c axis.
Conclusions:
- The synthesized Schiff base exhibits a defined molecular conformation stabilized by intramolecular hydrogen bonding.
- The crystal packing arrangement, driven by intermolecular hydrogen bonds, leads to the formation of one-dimensional chains.
- This study provides fundamental structural insights into brominated pyridine-based Schiff bases, relevant for further material design.
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