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Updated: Jun 1, 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
1,3-Bis(bromo-meth-yl)-2-nitro-benzene.
Summary
This study details the crystal structure of a novel dibrominated nitroarene compound, C(8)H(7)Br(2)NO(2), an intermediate crucial for synthesizing macrocycles. Its molecular geometry, featuring specific dihedral angles and trans conformations, closely approximates C2 symmetry.
Area of Science:
- Organic Chemistry
- Crystallography
- Chemical Synthesis
Background:
- Macrocycles are vital in various chemical and biological applications.
- Efficient synthesis of macrocyclic compounds requires well-defined intermediates.
- Understanding the structural properties of intermediates aids in optimizing synthetic routes.
Purpose of the Study:
- To elucidate the crystal structure of the title compound, C(8)H(7)Br(2)NO(2).
- To characterize the molecular geometry and conformation of this key intermediate.
- To provide structural insights for macrocycle synthesis.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed.
- The crystal structure was solved and refined.
- Geometric parameters, including dihedral angles and bond lengths/angles, were analyzed.
Main Results:
- The crystal structure of C(8)H(7)Br(2)NO(2) was determined.
- The nitro group (NO(2)) exhibits a dihedral angle of 65.07° relative to the arene ring.
- Bromo-methyl substituents adopt a trans conformation, leading to near C2 symmetry.
Conclusions:
- The determined structure provides a precise understanding of the intermediate's conformation.
- This structural information is valuable for designing and executing macrocycle synthesis.
- The near C2 symmetry may influence reactivity and subsequent cyclization steps.
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