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Updated: Jun 5, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
2,3-Bis(4-bromo-phen-yl)quinoxaline.
Fang-Fang Jian1, Ke-Fei Wang, Rui-Rui Zhuang
1New Materials and Function Coordination Chemistry Laboratory, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China.
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
Researchers synthesized a novel dibromo-quinoxaline derivative using a condensation reaction. Structural analysis revealed specific dihedral angles and confirmed stability through van der Waals forces in its crystal packing.
Area of Science:
- Organic Chemistry
- Crystallography
- Materials Science
Background:
- Quinoxaline derivatives are important heterocyclic compounds with diverse applications.
- Understanding the structure-property relationships of novel organic molecules is crucial for materials development.
Purpose of the Study:
- To synthesize and characterize a new dibromo-quinoxaline compound.
- To investigate the molecular geometry and crystal packing of the synthesized compound.
Main Methods:
- Synthesis via condensation reaction between 1-(3-bromo-phenyl)-2-(4-bromo-phenyl)ethane-1,2-dione and o-phenylenediamine.
- Refluxing in ethanol as the reaction medium.
- Structural analysis including bond lengths, angles, and dihedral angles.
Main Results:
- Successful synthesis of the target dibromo-quinoxaline compound (C(20)H(12)Br(2)N(2)).
- Molecular structure analysis showed normal bond lengths and angles.
- Key dihedral angles determined: 34.89° (between benzene rings), 57.23° and 36.75° (between benzene rings and quinoxaline system).
- Crystal packing is primarily stabilized by van der Waals forces.
Conclusions:
- The synthesized dibromo-quinoxaline derivative possesses a well-defined molecular structure.
- The compound exhibits specific conformational preferences indicated by dihedral angles.
- Van der Waals forces play a significant role in the solid-state arrangement of the molecule.
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