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Published on: April 27, 2017
1,3-Bis(2-meth-oxy-phen-yl)thio-urea.
Jason van Rooyen1, Richard Betz, Bernardus J A M van Brecht
1Nelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth 6031, South Africa.
Acta Crystallographica. Section E, Structure Reports Online
|January 6, 2012
Summary
This study details the crystal structure of a novel organic compound, C(15)H(16)N(2)O(2)S. Analysis reveals amide-type resonance and specific dihedral angles, with intermolecular hydrogen bonds influencing crystal packing.
Area of Science:
- Crystallography
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Understanding molecular interactions is crucial in crystal engineering.
- Thio-urea derivatives exhibit diverse chemical properties and applications.
- Aromatic ring interactions play a significant role in crystal lattice formation.
Purpose of the Study:
- To elucidate the crystal structure of the compound C(15)H(16)N(2)O(2)S.
- To investigate the presence and implications of amide-type resonance.
- To analyze intermolecular interactions, including hydrogen bonding and π-π stacking.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond lengths and angles provided insights into electronic properties.
- Dihedral angles were calculated to describe the spatial arrangement of molecular fragments.
- Intermolecular interactions were identified and characterized.
Main Results:
- The N-C(=S) bond lengths indicate significant amide-type resonance within the thio-urea moiety.
- Distinct dihedral angles were observed between the thio-urea unit and aromatic rings (59.80(5)° and 73.41(4)°), and between the aromatic rings (56.83(4)°).
- The crystal structure features inversion dimers formed by N-H⋯S hydrogen bonds and an N-H⋯π interaction involving an amino group.
- The shortest centroid-centroid distance between aromatic systems was 4.0958(8) Å.
Conclusions:
- The compound C(15)H(16)N(2)O(2)S exhibits characteristic thio-urea resonance and specific conformational preferences.
- Intermolecular N-H⋯S hydrogen bonding and N-H⋯π interactions are key factors in the observed crystal packing.
- The structural data provides a foundation for understanding the physical and chemical properties of this class of compounds.
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