![Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F51444.jpg&w=3840&q=50)
Surface-Modified Pd/CeO2 Single-Atom Catalyst Shows Increased Activity for Suzuki Cross-Coupling.
Audrey Vice1, Nicholas Langer1, Benjamin Reinhart2
1Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, Wisconsin 53201-1881, United States.
Inorganic Chemistry
|December 6, 2023
Summary
Organic monolayers enhance single-atom catalysts (SACs) for Suzuki coupling. Modifying palladium on ceria with catechol coatings significantly boosts catalytic activity and lowers activation energy, improving fine chemical synthesis.
Area of Science:
- Heterogeneous catalysis
- Materials science
- Organic synthesis
Background:
- Single-atom catalysts (SACs) offer high activity and separation ease but lack precise active site control.
- Homogeneous catalysts provide active site control via ligands but are difficult to separate.
- Organic monolayers present a novel strategy to functionalize catalyst supports.
Purpose of the Study:
- To investigate the impact of organic monolayer modification on SAC performance.
- To enhance the catalytic activity of palladium on ceria (Pd/CeO2) SACs for Suzuki cross-coupling.
- To explore the mechanism behind the observed catalytic improvements.
Main Methods:
- Synthesis of Pd/CeO2 SACs modified with catechol-type organic monolayers.
- Evaluation of catalytic activity for Suzuki cross-coupling reactions.
- Kinetic studies to determine activation energy and reaction rates.
Main Results:
- Catechol monolayer modification of Pd/CeO2 SACs significantly increased catalytic activity for Suzuki coupling.
- Activation energy was reduced from 49 ± 9 to 22 ± 5 kJ/mol.
- A four-fold rate enhancement was observed at 25 °C, attributed to π-π interactions.
Conclusions:
- Support modification with organic monolayers is an effective strategy to enhance SAC performance.
- Catechol monolayers improve Pd/CeO2 SACs for Suzuki coupling by lowering activation energy.
- This approach holds potential for broader applications of SACs in organic synthesis.
More Related Videos
Related Concept Videos
02:13Reduction of Alkenes: Catalytic Hydrogenation
12.1K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.1K
02:50Catalysis
27.0K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.0K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.7K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
7.7K
01:28Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
4.6K
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
4.6K
01:12Cycloaddition Reactions: MO Requirements for Photochemical Activation
2.1K
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
2.1K
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.3K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.3K