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Updated: Jun 1, 2026
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Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Ethyl 2-(2,3,4,5,6-Penta-bromo-phen-yl)acetate
Summary
This study details the crystal structure of PBPEA, revealing its ethyl acetate group is nearly perpendicular to the benzene ring. Intermolecular bromine interactions were observed, influencing the crystal packing arrangement.
Area of Science:
- Organic Chemistry
- Crystallography
Background:
- Understanding the molecular geometry and intermolecular interactions of organic compounds is crucial for predicting their physical and chemical properties.
- Halogenated organic compounds, particularly those containing bromine, often exhibit unique packing motifs and intermolecular forces.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, PBPEA (C10H7Br5O2).
- To analyze the spatial arrangement of the ethyl acetate moiety relative to the benzene ring.
- To investigate intermolecular bromine-bromine (Br⋯Br) contacts and their influence on crystal packing.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional structure of PBPEA.
- Analysis of bond lengths, bond angles, and torsion angles provided insights into molecular conformation.
- Crystal structure data was used to identify and quantify intermolecular contacts.
Main Results:
- The ethyl acetate portion of PBPEA was found to be nearly orthogonal to the benzene ring, with a C-C-C-C torsion angle of 88.3(5)°.
- A significant intermolecular Br⋯Br contact was observed with a distance of 3.491(1) Å.
- The C-Br⋯Br angles were determined to be 173.4(2)° and 106.0(2)°, indicating specific directional interactions.
- The crystal was identified as an inversion twin.
Conclusions:
- The crystal structure of PBPEA is characterized by a near-orthogonal orientation between the ethyl acetate and benzene moieties.
- Intermolecular Br⋯Br interactions play a role in the observed crystal packing, suggesting potential for halogen bonding.
- The presence of an inversion twin highlights the importance of careful crystallographic analysis.
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