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5-Hy-droxy-2-{(E)-[(3-nitro-phen-yl)iminio]meth-yl}phenolate
Acta Crystallographica. Section E, Structure Reports Online
|September 13, 2012
Summary
This study details the crystal structure of a zwitterionic compound, revealing shorter phenolate C-O bonds and longer azomethine C=N bonds. Molecular conformation is stabilized by intramolecular hydrogen bonds and intermolecular interactions in crystal chains.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular Structure
Background:
- Zwitterionic tautomers are crucial in understanding molecular properties.
- The crystal structure of organic compounds provides insights into bonding and intermolecular forces.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(13)H(10)N(2)O(4).
- To analyze bond lengths, molecular planarity, and intermolecular interactions.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, bond angles, dihedral angles, and hydrogen bonding networks.
Main Results:
- The compound crystallizes as a zwitterionic tautomer with a nearly planar structure.
- Observed phenolate C-O(-) bond length of 1.296(2) Å and azomethine C=N bond length of 1.314(2) Å.
- Intramolecular N-H⋯O hydrogen bonds stabilize the conformation, while intermolecular O-H⋯O and C-H⋯O hydrogen bonds form double-stranded chains with π-π interactions.
Conclusions:
- The crystal structure reveals significant deviations from typical bond lengths due to zwitterionic character.
- Intermolecular hydrogen bonding and π-π stacking play a key role in the crystal packing and stability.
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