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Updated: Jun 1, 2026
08:43
Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
4-Chloro-N-(2-pyrid-yl)aniline.
Wan Ainna Mardhiah Wan Saffiee1, Azila Idris, Zaharah Aiyub
1Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Summary
This study reveals the crystal structure of a C(11)H(9)ClN(2) compound, detailing molecular arrangements and dihedral angles. The molecules self-assemble into dimers through specific hydrogen bonding interactions.
Area of Science:
- Crystallography
- Molecular Chemistry
Background:
- Understanding the solid-state structure of organic compounds is crucial for predicting their physical and chemical properties.
- The specific arrangement of molecules influences intermolecular interactions and crystal packing.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(11)H(9)ClN(2).
- To analyze the dihedral angles between aromatic ring planes within the asymmetric unit.
- To investigate the intermolecular interactions, specifically dimer formation through hydrogen bonding.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of the crystallographic data provided precise measurements of bond lengths, bond angles, and dihedral angles.
Main Results:
- The asymmetric unit contains two molecules of C(11)H(9)ClN(2).
- Dihedral angles between the aromatic ring planes were measured as 41.84(12)° and 49.24(12)°.
- The two molecules form a dimer mediated by a pair of N-H⋯N hydrogen bonds.
Conclusions:
- The crystal structure of C(11)H(9)ClN(2) has been successfully determined.
- The compound exhibits specific molecular conformations characterized by distinct dihedral angles.
- Hydrogen bonding plays a significant role in the self-assembly of these molecules into dimers in the solid state.
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01:26Physical Properties of Amines
Amines with low molecular weight are usually gaseous at room temperature, while those with high molecular weight are liquid or solids in nature. Usually, low molecular weight amines have a rotten fish-like smell. Diamines typically have a pungent smell. For instance, cadaverine and putrescine, depicted in Figure 1, are two molecules responsible for decaying tissue.
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One of the methods for preparing symmetrical or unsymmetrical acid anhydrides involves the treatment of acid chlorides with the sodium salt of carboxylic acids. The reaction proceeds via a nucleophilic acyl substitution.
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
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01:18Basicity of Aromatic Amines
The basicity of aromatic amines is much weaker than that of aliphatic amines due to the involvement of the lone pair of electrons over the N atom in resonance with the aryl rings. Generally, the electron-donating ability of any substituents on the aryl ring of aromatic amines increases the basicity of the amine by increasing electron density, and hence the availability of lone pair on the nitrogen. On the other hand, electron-withdrawing functional groups on the aryl ring of amines decrease the...
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