Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Cycloaddition Reactions: Overview01:16

Cycloaddition Reactions: Overview

3.5K
Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
3.5K
Turnover Number and Catalytic Efficiency01:19

Turnover Number and Catalytic Efficiency

21.6K
The turnover number of an enzyme is the maximum number of substrate molecules it can transform per unit time. Turnover numbers for most enzymes range from 1 to 1000 molecules per second. Catalase has the known highest turnover number, capable of converting up to 2.8×106 molecules of hydrogen peroxide into water and oxygen per second. Lysozyme has the lowest known turnover number of half a molecule per second.
Chymotrypsin is a pancreatic enzyme that breaks down proteins during digestion....
21.6K
Catalytically Perfect Enzymes01:07

Catalytically Perfect Enzymes

5.1K
The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at high-speed. Their catalytic efficiency values range from 108-109 M-1s-1. These enzymes are also called 'diffusion-controlled' as the only rate-limiting step in the catalysis is that of the substrate diffusion into the active site. Examples include triose phosphate isomerase, fumarase, and superoxide dismutase.
 
Most enzymes...
5.1K
Cycloaddition Reactions: MO Requirements for Photochemical Activation01:12

Cycloaddition Reactions: MO Requirements for Photochemical Activation

2.7K
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.
2.7K
Cycloaddition Reactions: MO Requirements for Thermal Activation01:16

Cycloaddition Reactions: MO Requirements for Thermal Activation

4.5K
Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
4.5K
Reduction of Alkenes: Catalytic Hydrogenation02:13

Reduction of Alkenes: Catalytic Hydrogenation

14.1K
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...
14.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Asymmetric Decarboxylative Protonation and Deuteration of Cyanoacetic Acids Using an Organometallic Proton Shuttle.

Journal of the American Chemical Society·2026
Same author

Rhodium-Catalyzed Desymmetric Addition of Boronic Acids to Malononitriles.

Journal of the American Chemical Society·2026
Same author

Homochiral Metal-Organic Framework Featuring Transformable Helical and Sheeted Structures.

Journal of the American Chemical Society·2025
Same author

Tri- and Tetra-<i>ortho</i>-Substituted Biaryls via Lithium Cuprate-Catalyzed Reductive Desymmetrization of Isophthaldehydes.

Journal of the American Chemical Society·2025
Same author

Enantioselective Zn-catalyzed hydrophosphinylation of nitrones: an efficient approach for constructing chiral α-hydroxyamino-phosphine oxides.

Chemical science·2025
Same author

Cobalt-catalysed desymmetrization of malononitriles via enantioselective borohydride reduction.

Nature chemistry·2024

Related Experiment Video

Updated: Feb 3, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
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

10.2K

Catalytic palladium-oxyallyl cycloaddition.

Barry M Trost1, Zhongxing Huang2, Ganesh M Murhade2

  • 1Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA. bmtrost@stanford.edu.

Science (New York, N.Y.)
|November 3, 2018
PubMed
Summary
This summary is machine-generated.

Researchers developed a novel palladium-catalyzed (3+2) cycloaddition using a Pd-oxyallyl intermediate. This method efficiently synthesizes diverse tetrahydrofuran skeletons, overcoming limitations of traditional oxyallyl cation chemistry.

More Related Videos

Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination
11:16

Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination

Published on: August 18, 2020

6.0K
Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles
11:54

Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles

Published on: June 25, 2018

10.8K

Related Experiment Videos

Last Updated: Feb 3, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
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

10.2K
Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination
11:16

Preparation of Silver-Palladium Alloyed Nanoparticles for Plasmonic Catalysis under Visible-Light Illumination

Published on: August 18, 2020

6.0K
Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles
11:54

Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles

Published on: June 25, 2018

10.8K

Area of Science:

  • Organic Synthesis
  • Catalysis
  • Medicinal Chemistry

Background:

  • Chemoselective cycloaddition reactions are crucial for constructing complex ring systems in organic synthesis.
  • Oxyallyl cations typically undergo (4+3) cycloadditions, limiting their utility in forming five-membered rings.
  • Developing new synthetic pathways for accessing five-membered skeletons remains a significant challenge.

Purpose of the Study:

  • To explore novel cycloaddition reactions for synthesizing five-membered ring systems.
  • To investigate the use of palladium catalysis in oxyallyl cation chemistry.
  • To develop a method for accessing tetrahydrofuran skeletons via a (3+2) cycloaddition pathway.

Main Methods:

  • Generation of a palladium-oxyallyl intermediate from a tailored precursor using a Pd(0) catalyst.
  • Reaction of the Pd-oxyallyl intermediate with conjugated dienes in a (3+2) cycloaddition.
  • Subsequent palladium-catalyzed conversion of tetrahydrofuran adducts to cyclopentanones.

Main Results:

  • A novel Pd-catalyzed (3+2) cycloaddition reaction was achieved, yielding diverse tetrahydrofuran skeletons.
  • The reaction proceeds via a stepwise pathway involving Pd-allyl transfer and ring closure, overriding conventional (4+3) selectivity.
  • The resulting heterocycles can be readily transformed into carbocyclic cyclopentanones.

Conclusions:

  • This study presents a new strategy for accessing five-membered rings using palladium catalysis.
  • The developed method offers a versatile route to substituted tetrahydrofurans and cyclopentanones.
  • This approach expands the synthetic utility of oxyallyl intermediates in organic chemistry.