3-(2-Ethyl-2-phenyl-hydrazin-1-yl-idene)indolin-2-one
Uzma Ashiq1, Rifat Ara Jamal, Hina Ismail
1Department of Chemistry, University of Karachi, Karachi 75270, Pakistan.
Acta Crystallographica. Section E, Structure Reports Online
|March 12, 2013
Summary
The study details the molecular structure of a C16H15N3O compound, revealing a specific dihedral angle between its indole and phenyl rings. This conformation is stabilized by intramolecular hydrogen bonding, influencing its crystal packing.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- Understanding molecular conformation is crucial in organic chemistry.
- Intermolecular and intramolecular interactions dictate crystal packing and properties.
- The indole and phenyl ring systems are common motifs in biologically active molecules.
Purpose of the Study:
- To elucidate the precise three-dimensional structure of the C16H15N3O compound.
- To analyze the conformational preferences and stabilizing interactions within the molecule.
- To describe the crystal packing arrangement and hydrogen bonding network.
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 analysis of intramolecular and intermolecular hydrogen bonding interactions.
Main Results:
- The dihedral angle between the indole and phenyl ring systems was determined to be 14.49(9)°.
- An intramolecular C-H⋯O interaction was identified, forming an S(7) ring and stabilizing the molecular conformation.
- In the crystal lattice, inversion dimers linked by N-H⋯O hydrogen bonds were observed, forming R2(2)(8) loops.
Conclusions:
- The molecular conformation of the C16H15N3O compound is defined by the relative orientation of its indole and phenyl rings.
- Intramolecular hydrogen bonding plays a significant role in maintaining this specific conformation.
- The crystal structure is characterized by a network of intermolecular hydrogen bonds forming inversion dimers.
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