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Updated: Jul 15, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
2-{[(4-Methylphenyl)sulfonyl]amino}phenyl 4-methylbenzenesulfonate
G L Morgans1, S M Scalzullo, M A Fernandes
1School of Chemistry, Molecular Sciences Institute, University of the Witwatersrand, PO Wits 2050, Johannesburg, South Africa.
Summary
This study reveals that a specific compound crystallizes with two molecular orientations, forming various hydrogen-bonded dimers. Additional interactions stabilize these structures, influencing crystal growth.
Area of Science:
- Crystallography
- Supramolecular Chemistry
- Organic Chemistry
Background:
- The crystallization behavior of organic compounds is crucial for understanding their solid-state properties.
- Polymorphism, the ability of a compound to crystallize in multiple forms, can significantly impact material characteristics.
- Hydrogen bonding and other intermolecular forces play a key role in dictating crystal packing and stability.
Purpose of the Study:
- To investigate the crystallographic structure of the title compound, C(20)H(19)NO(5)S(2).
- To analyze the formation and stability of different hydrogen-bonded dimer types resulting from co-existing molecular orientations.
- To elucidate the role of secondary interactions (C-H...O and C-H...pi) in stabilizing the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the crystal structure.
- Analysis of hydrogen bonding networks, including N-H...O interactions, was performed.
- Investigation of other intermolecular interactions such as C-H...O and C-H...pi was conducted.
Main Results:
- The title compound crystallizes as a mixture of two molecular orientations (Orient-A and Orient-B) in an approximately 2:1 ratio.
- Three types of N-H...O hydrogen-bonded dimers were identified: (Orient-A + Orient-A), (Orient-A + Orient-B), and (Orient-B + Orient-B).
- The (Orient-A + Orient-A) dimers are likely the most stable, while mixed dimers are more frequent. C-H...O and C-H...pi interactions further stabilize these arrangements, preventing conversion to a single orientation.
Conclusions:
- The co-existence of multiple molecular orientations in the crystal lattice is stabilized by a combination of primary hydrogen bonds and secondary interactions.
- The observed crystal structure highlights the complex interplay of intermolecular forces in directing the self-assembly of organic molecules.
- Understanding these packing motifs is essential for predicting and controlling the solid-state behavior of related compounds.
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