Related Experiment Video
Updated: May 11, 2026
19:58
Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
2-(4-Fluoro-benzyl-idene)propane-dinitrile: monoclinic polymorph
Ahmed M El-Agrody1, Mohamed A Al-Omar, Abd El-Galil E Amr
1Chemistry Department, Faculty of Science, King Khalid University, Abha 61413, PO Box 9004, Saudi Arabia ; Chemistry Department, Faculty of Science, Al-Azhar University, Nasr City, Cairo 11884, Egypt.
Summary
This study details a new monoclinic polymorph of C10H5FN2, distinct from its triclinic form. Structural analysis reveals near-coplanar atoms and specific intermolecular interactions in the crystal lattice.
Area of Science:
- Crystallography
- Solid-state chemistry
Background:
- Polymorphism in organic compounds can significantly alter physical and chemical properties.
- Previous research identified a triclinic (P-1) polymorph of C10H5FN2.
Purpose of the Study:
- To characterize a newly identified monoclinic (P21/c) polymorph of C10H5FN2.
- To compare the structural features and intermolecular interactions of the monoclinic and triclinic polymorphs.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the crystal structure of the monoclinic polymorph.
- Analysis of atomic planarity and torsion angles provided insights into molecular conformation.
- Intermolecular interactions, including C-H⋯N and C-F⋯π interactions, were investigated.
Main Results:
- The title compound, C10H5FN2, crystallizes as a monoclinic (P21/c) polymorph.
- The 13 non-hydrogen atoms in the monoclinic polymorph are nearly coplanar (r.m.s. deviation = 0.020 Å).
- Supramolecular layers are formed via C-H⋯N interactions, with C-F⋯π interactions connecting these layers.
Conclusions:
- The discovery of a new monoclinic polymorph expands the understanding of C10H5FN2's solid-state behavior.
- The distinct crystal packing and intermolecular interactions in the monoclinic form may lead to different material properties compared to the triclinic form.
More Related Videos
Related Concept Videos
02:18Conformations of Ethane and Propane
In an organic molecule, free rotation about the carbon-carbon single bond results in energetically different conformers of the molecule. Due to this rotation, called the internal rotation, ethane has two major conformations — staggered and eclipsed.
Staggered conformation is a low energy and more stable conformation with the C-H bonds on the front carbon placed at 60°dihedral angles relative to the C-H bonds on the back carbon, leading to a reduced torsional strain. In staggered ethane, the...
Staggered conformation is a low energy and more stable conformation with the C-H bonds on the front carbon placed at 60°dihedral angles relative to the C-H bonds on the back carbon, leading to a reduced torsional strain. In staggered ethane, the...
02:20Conformations of Butane
Unlike ethane and propane that have only two major conformations, butane has more than two conformers. The staggered form of butane in which the bulky methyl groups on the two carbons are placed on opposite sides, that is, at a dihedral angle of 180°, is the lowest energy, most stable form — called the anti conformer. This conformation is stabilized due to the absence of steric repulsion between the largely spaced out methyl groups. The other two staggered conformations are degenerate and have...
02:06Newman Projections
Different notations are used to represent the three-dimensional structure of molecules on two-dimensional surfaces. One of the most commonly used representations is the dash-wedge formula. The dashed wedges, solid wedges, and the plane lines indicate the groups situated behind the plane, coming out of the plane, and in the plane, respectively.
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as conformers.
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as conformers.
01:00Characteristics and Nomenclature of Homopolymers
Polymers that are made up of identical monomer units are called homopolymers. Only one repeating unit is involved in the construction of the homopolymer structure. For example, as depicted in Figure 1, polypropylene is a homopolymer constituted of propylene monomers. Here, the only repeating unit in the polymer chain is propylene.
02:29Conformations of Cycloalkanes
Adolf von Baeyer attempted to explain the instabilities of small and large cycloalkane rings using the concept of angle strain — the strain caused by the deviation of bond angles from the ideal 109.5° tetrahedral value for sp3 hybridized carbons. However, while cyclopropane and cyclobutane are strained, as expected from their highly compressed bond angles, cyclopentane is more strained than predicted, and cyclohexane is virtually strain-free. Hence, Baeyer’s theory that was based on the...
01:11Nomenclature of Aromatic Compounds with Multiple Substituents
When more than one substituent is present on the benzene ring, the IUPAC nomenclature depends on the number of substituents present.
For disubstituted benzene derivatives, with two groups attached to the benzene ring, three constitutional isomers are possible. For example, consider dimethyl benzene, often called xylene, where the second methyl group can be substituted at the second, third, or fourth carbon. The relative position of the substituents is represented by prefixes ortho, meta, or...
For disubstituted benzene derivatives, with two groups attached to the benzene ring, three constitutional isomers are possible. For example, consider dimethyl benzene, often called xylene, where the second methyl group can be substituted at the second, third, or fourth carbon. The relative position of the substituents is represented by prefixes ortho, meta, or...