3,4-Dimeth-oxy-N-(3-nitro-benzyl-idene)aniline
Summary
This study details the crystal structure of a compound with formula C(15)H(14)N(2)O(4). It reveals specific molecular arrangements and intermolecular interactions, including hydrogen bonds and pi-stacking.
Area of Science:
- Crystallography
- Organic Chemistry
- Molecular Structure
Background:
- Understanding molecular conformation and packing is crucial in solid-state chemistry.
- Substituent effects on aromatic systems influence crystal lattice formation.
- Intermolecular interactions dictate bulk material properties.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(15)H(14)N(2)O(4).
- To analyze the planarity of substituents and benzene rings within the molecule.
- To investigate the dihedral angles and spatial arrangement of independent molecules.
- To identify intermolecular interactions present in the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the crystal structure.
- Analysis of crystallographic data revealed two independent molecules in the asymmetric unit.
- Geometric parameters, including dihedral angles and substituent planarity, were calculated.
- Identification of intermolecular contacts, such as C-H⋯O hydrogen bonds and C-H⋯π interactions.
Main Results:
- The title compound crystallizes with two independent molecules in the asymmetric unit.
- Nitro and methoxy substituents are coplanar with their respective benzene rings in both molecules.
- Benzene rings exhibit near-coplanarity, with small dihedral angles (10.39(8)° and 5.95(8)°).
- Significant rotational differences exist between the two independent molecules (dihedral angles of 49.11(8)° and 63.93(8)°).
- Intermolecular C-H⋯O hydrogen bonds and weak C-H⋯π interactions were observed in the crystal structure.
Conclusions:
- The crystal structure provides detailed insights into the conformational preferences of the title compound.
- The observed planarity and dihedral angles highlight specific electronic and steric influences.
- Intermolecular interactions play a role in stabilizing the crystal packing.
- This structural characterization serves as a foundation for further studies on related compounds.
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The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...