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

Radical Reactivity: Overview01:11

Radical Reactivity: Overview

Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired molecule. These three...
Radical Reactivity: Steric Effects01:10

Radical Reactivity: Steric Effects

The presence of electron-donating, electron-withdrawing, or conjugating groups adjacent to a radical center, imparts electronic stabilization to the radicals. Examples of such electronically-stabilized radicals are triphenylmethyl, tetramethylpiperidine‐N‐oxide, and 2,2‐diphenyl‐1‐picrylhydrazyl. These radicals are remarkably stable and are known as persistent radicals. Some of the persistent radicals can even be isolated and purified.
Along with electronic factors, steric factors also account...
Radical Reactivity: Intramolecular vs Intermolecular01:33

Radical Reactivity: Intramolecular vs Intermolecular

Radical reactions can occur either intermolecularly or intramolecularly. In an intermolecular radical reaction, a nucleophilic radical adds to an electrophilic alkene or vice versa. In such reactions, the radical and generally the alkene, which is also called the radical trap, are two different molecules. Additionally, for such intermolecular reactions to occur, the radical trap must be active, present in an excess concentration, and the radical starting material must have a weak carbon–halogen...
Radical Reactivity: Nucleophilic Radicals01:16

Radical Reactivity: Nucleophilic Radicals

Radicals adjacent to electron-donating groups are called nucleophilic radicals. These radicals readily react with electrophilic alkenes. The SOMO–LUMO interactions are the driving force for the reaction, where the high-energy SOMO of the electron-rich, nucleophilic radicals interacts with the low-energy LUMO of the electron-deficient, electrophilic alkenes. Such SOMO–LUMO interactions are the basis of reactive radical traps, affecting the selectivity in radical reactions. For instance, consider...
Radical Formation: Overview01:03

Radical Formation: Overview

A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the latter, also known...
Transducer Mechanism: Enzyme-Linked Receptors01:27

Transducer Mechanism: Enzyme-Linked Receptors

Enzyme-linked receptors are cell-surface receptors acting as an enzyme or associating with an enzyme intracellularly. They make excellent drug targets. Drugs can bind to the extracellular ligand-binding domain or directly affect their enzymatic domain and alter their activity.
Major types that are helpful drug targets include:

You might also read

Related Articles

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

Sort by
Same author

Artificial Intelligence-Guided Discovery of Covalent Organic Frameworks for Next-Generation Polyfluoroalkyl Substances Removal.

ACS applied materials & interfaces·2026
Same author

Covalent Organic Frameworks with Intrinsic Pendant Aldehydes for Efficient Nitrate Electroreduction.

Small (Weinheim an der Bergstrasse, Germany)·2026
Same author

MassSeg-Framework: A Breast Mass Detection and Segmentation Framework Based on Deep Learning and an Active Contour Model.

Life (Basel, Switzerland)·2026
Same author

Insights into the Chemico-Biological Interactions of Natural Sesquiterpene Lactones with the Thiol-Redox Metabolism of Pathogenic Trypanosomatids.

ChemMedChem·2026
Same author

Manganese-Templated Nontrivial Structures for MRI and Therapy.

Journal of the American Chemical Society·2026
Same author

A Modular 3D-Printed Design to Investigate Prebiotic Chemical Systems in Hot Spring Pools.

Astrobiology·2026
Same journal

A rechargeable non-aqueous Mg-O<sub>2</sub> battery based on magnesium peroxide chemistry.

Nature chemistry·2026
Same journal

Setting a direction for molecular motors.

Nature chemistry·2026
Same journal

Driving movement in the field of molecular machines.

Nature chemistry·2026
Same journal

First ladies of chemistry.

Nature chemistry·2026
Same journal

How isoprene connects plants to global climate.

Nature chemistry·2026
Same journal

One-dimensional carbon chains free of end-capping groups.

Nature chemistry·2026
See all related articles

Related Experiment Video

Updated: Jun 6, 2026

Single-Molecule Surface-Enhanced Raman Scattering Measurements Enabled by Plasmonic DNA Origami Nanoantennas
10:43

Single-Molecule Surface-Enhanced Raman Scattering Measurements Enabled by Plasmonic DNA Origami Nanoantennas

Published on: July 21, 2023

Radically enhanced molecular recognition.

Ali Trabolsi1, Niveen Khashab, Albert C Fahrenbach

  • 1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.

Nature Chemistry
|December 3, 2010
PubMed
Summary
This summary is machine-generated.

Viologen radical cations form strong complexes with cyclobis(paraquat-p-phenylene), enabling new host-guest chemistry. This advances molecular machines by controlling mechanically interlocked molecules using electrochemical potentials.

More Related Videos

DNAzyme 10-23 - Based Nanomachines for Nucleic Acid Recognition
07:16

DNAzyme 10-23 - Based Nanomachines for Nucleic Acid Recognition

Published on: February 9, 2024

Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction
03:38

Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction

Published on: October 6, 2022

Related Experiment Videos

Last Updated: Jun 6, 2026

Single-Molecule Surface-Enhanced Raman Scattering Measurements Enabled by Plasmonic DNA Origami Nanoantennas
10:43

Single-Molecule Surface-Enhanced Raman Scattering Measurements Enabled by Plasmonic DNA Origami Nanoantennas

Published on: July 21, 2023

DNAzyme 10-23 - Based Nanomachines for Nucleic Acid Recognition
07:16

DNAzyme 10-23 - Based Nanomachines for Nucleic Acid Recognition

Published on: February 9, 2024

Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction
03:38

Aptamer-Based Target Detection Facilitated by a 3-Stage G-Quadruplex Isothermal Exponential Amplification Reaction

Published on: October 6, 2022

Area of Science:

  • Supramolecular Chemistry
  • Materials Science
  • Chemical Engineering

Background:

  • Viologen radical cations exhibit dimerization tendencies.
  • Host-guest chemistry traditionally involves neutral or charged species.
  • Mechanically interlocked molecules (MIMs) offer potential for molecular switches and machines.

Purpose of the Study:

  • To establish a novel recognition motif using viologen radical cation dimerization.
  • To explore the use of radical cation complexes in host-guest chemistry.
  • To demonstrate electrochemical control over mechanically interlocked molecules.

Main Methods:

  • Formation of inclusion complexes between viologen radical cations and cyclobis(paraquat-p-phenylene).
  • Synthesis and characterization of bistable and tristable [2]rotaxanes.
  • Electrochemical switching of rotaxane components by altering redox potentials.

Main Results:

  • A new complex involving three bipyridinium cation radicals was formed.
  • The study extends host-guest chemistry to radical cation guests.
  • Electrochemical potentials were used to switch the position of a cyclobis(paraquat-p-phenylene) ring in a tristable [2]rotaxane.

Conclusions:

  • Viologen dimerization provides a versatile recognition strategy for host-guest systems.
  • This approach enhances control over molecular switches and machines.
  • Electrochemical stimuli can precisely control the states of mechanically interlocked molecules.