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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-Diallyl-2-methyl-benzimidazolium bromide dihydrate
Summary
This study reveals delocalized bonds within a five-membered ring of a hydrated salt. Hydrogen bonds link the anion and water molecules, with disordered oxygen atoms in the water molecule.
Area of Science:
- Crystallography
- Solid-state chemistry
- Molecular structure
Background:
- Understanding the structural properties of hydrated salts is crucial for various chemical applications.
- Delocalized bonding affects molecular stability and reactivity.
- Site symmetry and hydrogen bonding play key roles in crystal packing.
Purpose of the Study:
- To elucidate the crystal structure and bonding characteristics of the title hydrated salt, C(14)H(17)N(2) (+)·Br(-)·2H(2)O.
- To investigate the implications of site symmetry on the cation and anion.
- To analyze the hydrogen bonding network involving the anion and water molecules.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
- Analysis of bond delocalization within the five-membered ring.
- Investigation of intermolecular interactions, including hydrogen bonding and site symmetry.
Main Results:
- The five-membered ring of the hydrated salt exhibits delocalized bonding.
- The cation is situated on a special position with m site symmetry.
- The anion and water molecules form a chain via O-H⋯O hydrogen bonds, with disordered water oxygen atoms.
Conclusions:
- The crystal structure reveals significant delocalization in the cation's ring system.
- Hydrogen bonding dictates the arrangement of anions and water molecules in the crystal lattice.
- The observed disorder in water molecules provides insights into crystal dynamics.
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