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Updated: Jun 1, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
N-(3-Bromo-phen-yl)quinazoline-4,6-diamine
De-Liang Li1, Yang Wu, Qiang Wang
1State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, People's Republic of China.
Summary
The crystal structure of C(14)H(11)BrN(4) reveals nearly planar fused rings stabilized by pi-pi stacking and hydrogen bonding interactions. These interactions are crucial for the compound's overall structural integrity.
Area of Science:
- Crystallography
- Organic Chemistry
- Materials Science
Background:
- Understanding the structural properties of heterocyclic compounds is essential for their application.
- Fused ring systems often exhibit unique electronic and physical characteristics.
- Brominated nitrogen-containing heterocycles are of interest due to their potential biological and material properties.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(14)H(11)BrN(4).
- To investigate the intermolecular interactions governing the stability of the crystal lattice.
- To analyze the planarity and dihedral angles of the fused ring system.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, bond angles, and dihedral angles.
- Identification and quantification of intermolecular interactions, including π-π stacking and hydrogen bonding.
Main Results:
- The title compound crystallizes with two independent molecules in the asymmetric unit.
- The fused benzene and pyrimidine rings exhibit near planarity, with small dihedral angles (1.26(14)° and 3.53(15)°).
- Significant π-π stacking interactions (centroid-centroid distances of 3.4736(19) and 3.5416(19) Å) and weak N-H⋯N and N-H⋯Br hydrogen bonds stabilize the crystal structure.
Conclusions:
- The crystal structure of C(14)H(11)BrN(4) is characterized by a nearly planar fused ring system.
- Intermolecular π-π stacking and hydrogen bonding are key factors contributing to the observed crystal packing and stability.
- The findings provide fundamental insights into the solid-state behavior of this brominated heterocyclic compound.
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