2,3-Dimethyl-N-[(E)-4-nitro-benzyl-idene]aniline
Summary
This study details the crystal structure of C(15)H(14)N(2)O(2), revealing specific dihedral angles between aromatic rings and the nitro group. Molecules engage in aromatic π-π stacking interactions within the crystal lattice.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular interactions
Background:
- Understanding molecular conformation and intermolecular forces is crucial in solid-state chemistry.
- Aromatic π-π stacking significantly influences crystal packing and material properties.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(15)H(14)N(2)O(2).
- To analyze the spatial arrangement of aromatic rings and the nitro group.
- To investigate intermolecular interactions, specifically π-π stacking, in the crystalline state.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Geometric parameters, including dihedral angles, were precisely measured.
- Intermolecular distances and interactions were analyzed.
Main Results:
- The dihedral angle between the aromatic rings was determined to be 24.52(5)°.
- The dihedral angle between the nitro group and its parent benzene ring was found to be 9.22(16)°.
- Significant aromatic π-π stacking interactions were observed, with centroid-centroid separations of 3.8158(14) Å and 3.9139(14) Å.
Conclusions:
- The crystal structure of C(15)H(14)N(2)O(2) exhibits specific conformational preferences.
- Aromatic π-π stacking is a key stabilizing interaction in the crystal lattice of this compound.
- These findings contribute to the understanding of structure-property relationships in organic crystalline materials.
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01:10Nomenclature of Aryl and Heterocyclic Amines
The simplest aromatic amine is phenylamine, which contains an –NH2 functionality directly attached to an aromatic ring. The name aniline is designated for this skeleton. As shown in Figure 1, the common names of the functionalized anilines involve prefixes ortho-, meta-, and para- to indicate the substitution position. Different functionalized aniline derivatives also have notable trivial names.
01:202° Amines to N-Nitrosamines: Reaction with NaNO2
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
01:17Nomenclature of Primary Amines
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01:20Electrophilic Aromatic Substitution: Nitration of Benzene
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01:371° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
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