Boosting Gold(I) Catalysis via Weak Interactions: New Fine-Tunable Impy Ligands
Riccardo Pedrazzani1, Angela Pintus1, Roberta De Ventura1
1Dipartimento di Chimica "Giacomo Ciamician", Alma Mater Studiorum, Via Selmi 2, 40126 Bologna, Italy.
ACS Organic & Inorganic Au
|March 1, 2023
Summary
Modular N-heterocyclic carbene gold(I) complexes with tunable catalytic properties were synthesized. Introducing specific aromatic groups fine-tuned reactivity, notably accelerating gold(I)-catalyzed reactions of unsaturated hydrocarbons.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Materials Science
Background:
- N-heterocyclic carbenes (NHCs) are versatile ligands in organometallic chemistry.
- Gold(I) complexes are known catalysts for various organic transformations.
- Fine-tuning ligand structure is crucial for controlling catalytic activity.
Purpose of the Study:
- To synthesize and characterize a series of modular NHC-Au(I) complexes.
- To investigate the impact of substituents on the NHC ligand on catalytic properties.
- To evaluate the performance of these complexes in gold(I)-catalyzed reactions.
Main Methods:
- Synthesis of modular ImPy-carbene-Au(I) complexes.
- Solid-state and solution characterization (e.g., NMR, X-ray crystallography).
- Evaluation of catalytic activity in electrophilic activations of unsaturated hydrocarbons.
Main Results:
- Successfully synthesized and characterized a range of NHC-Au(I) complexes.
- Demonstrated that oligoaryl substituents at the C5-position of the ImPy core influence catalytic properties.
- Observed a significant acceleration in gold(I)-catalyzed reactions when a CF3-containing aromatic ring was incorporated.
Conclusions:
- Modular NHC-Au(I) complexes offer tunable and predictable catalytic behavior.
- Ligand design, specifically the incorporation of specific aromatic units, is key to enhancing catalytic efficiency.
- These findings provide a platform for developing more effective gold catalysts.
Related Concept Videos
02:51Metal-Ligand Bonds
21.2K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
21.2K
01:09Complexation Equilibria: Factors Influencing Stability of Complexes
437
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
437
01:20Immunogold Electron Microscopy
4.1K
Immunoelectron microscopy utilizes immunogold labeling of endogenous proteins with specific antibodies to detect and localize these proteins in cells and tissues. The procedure provides insights into the distribution and quantification of protein under different stimulation conditions offering clues about their functions. Conjugating highly electron-dense gold particles with primary or secondary antibodies allow antigen detection on and within cells, with high resolution and specificity.
4.1K
01:13Introduction to Mechanisms of Enzyme Catalysis
8.4K
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes...
8.4K
02:58Crystal Field Theory - Octahedral Complexes
27.0K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
27.0K
02:40Ligand Binding Sites
13.0K
Proteins are dynamic macromolecules that carry out a wide variety of essential processes; however, the activities of most proteins depend on their interactions with other molecules or ions, known as ligands.
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
13.0K