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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
N-(3-Bromo-phen-yl)-3,4,5-trimethoxy-benzamide
Summary
This study details the crystal structure of a bromo- and meth-oxy-substituted aromatic compound. Molecular geometry and hydrogen bonding influence its crystal packing, revealing insights into intermolecular interactions.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is crucial for predicting their properties and reactivity.
- Aromatic compounds with diverse substituents offer complex structural motifs that warrant detailed investigation.
- Crystal packing forces significantly influence the bulk properties of solid-state organic materials.
Purpose of the Study:
- To elucidate the precise molecular geometry and crystal packing of a novel bromo- and meth-oxy-substituted aromatic compound.
- To analyze the spatial orientation of substituent groups (amide, methoxy) relative to the aromatic rings.
- To identify the intermolecular interactions, specifically hydrogen bonding, responsible for the observed crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the atomic coordinates and unit cell parameters.
- Geometric parameters, including dihedral angles between aromatic rings and substituent orientations, were calculated.
- Analysis of intermolecular contacts, particularly N-H⋯O hydrogen bonds, was performed to understand crystal stabilization.
Main Results:
- The dihedral angle between the two aromatic rings in the title compound (C(16)H(16)BrNO(4)) was determined to be 7.74(18)°.
- The amide group exhibited significant tilt angles (36.3(8)° and 35.2(8)°) relative to the substituted aromatic rings.
- Meta-methoxy groups were nearly coplanar with the aromatic ring, while the para-methoxy group was significantly displaced (-72.5(4)°).
- Crystal packing is characterized by N-H⋯O hydrogen bonds forming molecular chains along the b-axis.
Conclusions:
- The study provides a detailed structural characterization of the title compound, highlighting the interplay between aromatic ring orientation and substituent positioning.
- The observed molecular conformation and the significant displacement of the para-methoxy group are key structural features.
- Intermolecular N-H⋯O hydrogen bonding plays a critical role in stabilizing the crystal structure, leading to the formation of extended chains.
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