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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
4-[Bis(4-fluorophenyl)methyl]piperazin-1-ium 2-(2-phenylethyl)benzoate
Acta Crystallographica. Section E, Structure Reports Online
|November 9, 2011
Summary
This study details the crystal structure of a salt formed from a 1,4-diaza-cyclo-hexane derivative and a carboxylic acid. The structure reveals specific conformations and intermolecular interactions, including hydrogen bonds and C-H contacts, forming layered crystal structures.
Area of Science:
- Crystallography
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Salts derived from heterocyclic amines and carboxylic acids are important in various chemical applications.
- Understanding the solid-state structure of such salts is crucial for predicting their physical and chemical properties.
Purpose of the Study:
- To determine and analyze the crystal structure of the title salt, C(17)H(19)F(2)N(2)(+.)C(15)H(13)O(2)(-).
- To investigate the conformational preferences of the cation and anion and the intermolecular interactions within the crystal lattice.
Main Methods:
- Single-crystal X-ray diffraction was employed to elucidate the crystal structure.
- Analysis of bond lengths, bond angles, dihedral angles, and intermolecular contacts (hydrogen bonds, van der Waals forces).
Main Results:
- The asymmetric unit contains two formula units of the salt.
- The cation features a protonated secondary amine and six-membered heterocycles in chair conformations.
- Fluorophenyl rings in cations and aromatic rings in anions exhibit specific dihedral angles, and layered structures are formed via N-H⋯O, C-H⋯F, and C-H⋯O interactions.
Conclusions:
- The study provides a detailed crystallographic description of the title salt.
- The observed hydrogen bonding and C-H⋯F/O contacts are key to the formation of the observed layered crystal architecture.
- This structural information contributes to the understanding of molecular packing in organic salts.
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