Synthesis and characterization of Pd/NHCF complexes with fluorinated aryl groups
Darya O Prima1, Roman O Pankov1, Alexander Yu Kostyukovich1
1Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia. val@ioc.ac.ru.
Dalton Transactions (Cambridge, England : 2003)
|June 16, 2022
Summary
Researchers developed a new method for synthesizing stable fluorine-containing imidazolium salts and their palladium complexes (Pd/NHCF). Fluorine substitution minimally impacts Pd-NHC bonding but slightly weakens the trans influence, strengthening Pd-Solv bonds.
Area of Science:
- Organometallic Chemistry
- Fluorine Chemistry
- Catalysis
Background:
- Instability of fluorine-containing diazadienes hinders synthesis.
- Need for novel ligands in catalysis and materials science.
Purpose of the Study:
- Efficient synthesis of fluorine-substituted imidazolium salts (NHCF).
- Preparation and characterization of new palladium complexes with NHCF ligands.
- Investigate the electronic effects of fluorine on Pd-NHC bonding and ligand properties.
Main Methods:
- Synthesis of fluorine-containing imidazolium salts.
- Complexation with palladium salts to form Pd/NHCF complexes.
- Computational and structural studies (e.g., DFT, X-ray crystallography).
Main Results:
- Successful synthesis of novel fluorine-substituted imidazolium salts and Pd/NHCF complexes.
- Fluorine substitution slightly decreases σ-donor and increases π-acceptor properties of NHC ligands.
- Pd-NHC bonding energy remains largely unchanged due to compensating electronic effects.
- Weakened trans influence of NHCF ligands observed, strengthening Pd-Solv bonds.
Conclusions:
- A straightforward synthetic route to novel Pd/NHCF complexes was established.
- Fluorine substitution offers tunable electronic properties for NHC ligands.
- These findings contribute to the design of new organometallic complexes for catalysis and materials.
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