(E)-N-(Anthracen-9-yl-methyl-idene)-4-nitro-aniline
Acta Crystallographica. Section E, Structure Reports Online
|November 8, 2011
Summary
This study details the molecular structure of C(21)H(14)N(2)O(2), revealing a near-planar anthracenyl system. Crystal packing is influenced by intramolecular hydrogen bonds and significant pi-pi interactions, crucial for understanding molecular assembly.
Area of Science:
- Crystallography
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is fundamental to predicting their properties and reactivity.
- The study of intermolecular forces, such as hydrogen bonding and pi-pi interactions, is essential for comprehending crystal packing and material properties.
Purpose of the Study:
- To elucidate the crystal structure and molecular geometry of the title compound, C(21)H(14)N(2)O(2).
- To investigate the nature of intramolecular interactions and their role in molecular conformation.
- To analyze the intermolecular interactions governing the crystal packing.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the precise atomic coordinates and bond lengths/angles.
- Analysis of the crystal structure included the identification of hydrogen bonding motifs and pi-pi stacking interactions.
- Geometric parameters such as dihedral angles and deviations from planarity were calculated.
Main Results:
- The anthracenyl moiety exhibits approximate planarity with a maximum deviation of 0.056(4) Å.
- A dihedral angle of 73.6(1)° was observed between the anthracenyl system and the benzene ring.
- An intramolecular C-H⋯N hydrogen bond was identified, forming an S(6) ring.
- Crystal packing is significantly influenced by C-H⋯π and π-π interactions, with centroid-centroid distances ranging from 3.656(1) to 3.716(2) Å.
Conclusions:
- The molecule C(21)H(14)N(2)O(2) possesses a defined three-dimensional structure characterized by a twisted conformation between the anthracenyl and benzene units.
- Intramolecular hydrogen bonding plays a role in stabilizing the molecular conformation.
- Intermolecular C-H⋯π and π-π interactions are key factors in the observed crystal packing, influencing the solid-state arrangement.
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01:202° Amines to N-Nitrosamines: Reaction with NaNO2
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01:19Diazonium Group Substitution: –OH and –H
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01:11Nomenclature of Carboxylic Acid Derivatives: Amides and Nitriles
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The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.