Related Experiment Video
Updated: Jun 10, 2025
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
9.6K
Revisiting Isomerism in Square Planar Palladium NHC Complexes with NacAc Chelators.
Dinh Cao Huan Do1, Han Vinh Huynh1
1Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore 117453, Republic of Singapore.
Inorganic Chemistry
|October 17, 2024
Summary
The Huynh electronic parameter for chelators (HEP2) effectively quantifies bidentate ligand donor ability in palladium complexes. This study validates HEP2 with diverse β-ketiminato ligands, confirming its reliability for inorganic chemistry applications.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Coordination Chemistry
Background:
- Quantifying ligand donor ability in inorganic chemistry is challenging.
- The Huynh electronic parameter for chelators (HEP2) offers a method for this quantification.
- Previous applications of HEP2 have been limited in scope.
Purpose of the Study:
- To extend the ligand scope for the HEP2 parameter.
- To scrutinize the soundness and practicality of HEP2 with β-ketiminato ligands.
- To explore isomerism in palladium(II) complexes with unsymmetrical ligands.
Main Methods:
- Synthesis of palladium(II) complexes with β-ketiminato (NacAc) ligands.
- Utilizing the HEP2 parameter to quantify ligand donor ability.
- Investigating isomerism through experimental and theoretical calculations.
- Correlating HEP2 values with Hammett constants.
Main Results:
- Successfully applied HEP2 to a diverse set of seven β-ketiminato chelators.
- Observed and analyzed isomerism in square planar Pd(II) products, influenced by N-aryl substituents.
- Demonstrated a strong correlation between HEP2 values and σₚ Hammett constants for both isomers.
Conclusions:
- The HEP2 parameter is a reliable and practical tool for quantifying bidentate ligand donor ability.
- The study expands the utility of HEP2 to a new class of ligands.
- The findings reinforce the validity of HEP2 as a modern quantitative methodology in inorganic chemistry.
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