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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
Benzyl-ethyl-dimethyl-ammonium bromide.
Maciej Hodorowicz1, Katarzyna Stadnicka
1Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland.
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
The crystal structure of a quaternary ammonium salt was determined. Methyl groups in the salt form weak hydrogen bonds, creating a three-dimensional network.
Area of Science:
- Crystal structure analysis
- Supramolecular chemistry
- Materials science
Background:
- Quaternary ammonium salts are known for their amphiphilic properties.
- Alkyl chain length significantly influences the activity of these salts.
- Understanding crystal packing is crucial for predicting material properties.
Purpose of the Study:
- To determine the crystal structure of C(11)H(18)N(+)·Br(-).
- To investigate the role of alkyl chain length in the amphiphilic activity of quaternary ammonium salts.
- To analyze the intermolecular interactions within the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was used to determine the crystal structure.
- Analysis of hydrogen bonding networks, specifically C-H⋯Br interactions.
- Examination of the three-dimensional network formed by ionic contacts.
Main Results:
- The crystal structure of C(11)H(18)N(+)·Br(-) was successfully elucidated.
- A three-dimensional network of ionic contacts was observed.
- Weak C-H⋯Br hydrogen bonds, with donor-acceptor distances of 3.757(2)-3.959(2) Å, were identified, with methyl groups acting as donors.
Conclusions:
- The crystal structure provides insights into the intermolecular forces governing quaternary ammonium salts.
- The observed hydrogen bonding network contributes to the overall structural stability.
- This study contributes to understanding structure-activity relationships in amphiphilic quaternary ammonium salts.
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