(E)-N-(3,3-Diphenyl-allyl-idene)-4-nitro-aniline
Yong Koo Kang1, Yong Seo Cho, Jae Kyun Lee
1Center for Neuro-Medicine, Korea Institute of Science & Technology, Hwarangro 14-gil, Seongbuk-gu, Seoul 136-791, Republic of Korea.
Acta Crystallographica. Section E, Structure Reports Online
|November 6, 2012
Summary
This study details the molecular structure of a novel organic compound, C(21)H(16)N(2)O(2). It reveals specific dihedral and torsion angles, offering insights into its three-dimensional chemical conformation and potential applications.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is crucial for predicting their properties and reactivity.
- Crystallographic studies provide precise structural data, including bond lengths, bond angles, and dihedral angles.
Purpose of the Study:
- To elucidate the precise molecular geometry of the title compound, C(21)H(16)N(2)O(2).
- To quantify the spatial relationships between the aromatic rings and the imine group within the molecule.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the atomic coordinates.
- Analysis of the crystal structure data to calculate key geometric parameters.
Main Results:
- The dihedral angle between the 4-nitro-phenyl ring and one phenyl ring is 57.3(5)°.
- The dihedral angle between the 4-nitro-phenyl ring and the second phenyl ring is 16.8(6)°.
- A C-C-N-C torsion angle of -24.9(3)° was observed for the imine group.
Conclusions:
- The title compound exhibits a non-planar conformation due to significant dihedral angles between its phenyl rings.
- The observed torsion angle of the imine group provides specific information about its local geometry.
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01:19Diazonium Group Substitution: –OH and –H
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
01:10Nomenclature of Aryl and Heterocyclic Amines
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01:371° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
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