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Updated: May 13, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
N-(2,5-Dimeth-oxy-phen-yl)-6-nitro-quinazolin-4-amine
Syed Muhammad Saad1, Imran Khan, Shahnaz Perveen
1H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
Acta Crystallographica. Section E, Structure Reports Online
|March 12, 2013
Summary
This study details the crystal structure of a C16H14N4O4 molecule, revealing a planar quinazoline ring and intra-molecular hydrogen bonding. Molecular chains form in the crystal via inter-molecular hydrogen bonds and pi-pi stacking interactions.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular Structure
Background:
- Understanding molecular conformation and intermolecular interactions is crucial in crystal engineering.
- Quinazoline derivatives are important scaffolds in medicinal chemistry and materials science.
- Detailed structural analysis provides insights into molecular packing and solid-state properties.
Purpose of the Study:
- To elucidate the crystal structure of the molecule C16H14N4O4.
- To investigate the conformational preferences and stabilizing interactions within the molecule.
- To characterize the intermolecular interactions governing crystal packing.
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 provided conformational information.
- Identification and analysis of hydrogen bonds and π-π stacking interactions were performed.
Main Results:
- The quinazoline ring is nearly planar with a dihedral angle of 2.73° relative to the benzene ring.
- An intramolecular C-H⋯N hydrogen bond stabilizes the molecular conformation.
- Intermolecular C-H⋯O hydrogen bonds link molecules into chains along the b-axis.
- π-π stacking occurs between substituted benzene rings with centroid-centroid distances ranging from 3.64 to 3.71 Å.
Conclusions:
- The crystal structure of C16H14N4O4 is characterized by planar quinazoline and benzene rings, stabilized by intramolecular hydrogen bonding.
- Intermolecular interactions, including hydrogen bonding and π-π stacking, dictate the observed crystal packing.
- The findings contribute to the understanding of structure-property relationships in quinazoline-based compounds.
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