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: Steric Effects01:10

Radical Reactivity: Steric Effects

2.3K
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...
2.3K
Radical Reactivity: Overview01:11

Radical Reactivity: Overview

2.6K
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...
2.6K
Radical Reactivity: Nucleophilic Radicals01:16

Radical Reactivity: Nucleophilic Radicals

2.6K
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...
2.6K
Radical Reactivity: Electrophilic Radicals01:02

Radical Reactivity: Electrophilic Radicals

2.3K
Radicals adjacent to electron‐withdrawing groups are called electrophilic radicals. These radicals readily react with nucleophilic alkenes. For example, the malonate radical, in which the radical center is flanked by two electron‐withdrawing groups, reacts readily with butyl vinyl ether, which consists of an electron‐donating oxygen substituent. The reaction between electrophilic malonate radical and nucleophilic vinyl ether is favored because the radical has a...
2.3K
Regioselectivity of Electrophilic Additions-Peroxide Effect02:35

Regioselectivity of Electrophilic Additions-Peroxide Effect

10.1K
In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.
10.1K
Radical Formation: Elimination00:51

Radical Formation: Elimination

2.1K
Another method of radical formation is the elimination process. It is the opposite of the addition route and is driven by the instability of the radical. For example, as depicted in Figure 1, dibenzoyl peroxide yields a pair of unstable radicals upon homolysis. Given its instability, this radical spontaneously undergoes elimination via a C–C bond cleavage to form a relatively more stable phenyl radical. The mechanism involves cleavage of the bond between the α and β positions with respect...
2.1K

You might also read

Related Articles

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

Sort by
Same author

Molecular Boron-Phosphides: From Stable Monomers to Aromaticity-Tunable Smallest Neutral Metallacycles.

Inorganic chemistry·2026
Same author

A Cerium Yldiide Complex with a Ce<math><mstyle><mtable><mtr><mtd><mo>←</mo></mtd></mtr><mtr><mtd><mo>←</mo></mtd></mtr></mtable></mstyle></math>C Double Dative Bond.

Inorganic chemistry·2026
Same author

Homoleptic and Heteroleptic Borylones L1-B(Ph)-L2.

Angewandte Chemie (International ed. in English)·2026
Same author

Redox-Active Doubly Boron-Doped Indenofluorenes: Isomer-Directed Access to Open- and Closed-Shell Electronic States Induces Strong Near-Infrared Activity.

Journal of the American Chemical Society·2026
Same author

Reactions of diazoboranes with oxygen enables the synthesis and isolation of dioxaboriranes.

Nature chemistry·2026
Same author

Homoleptic and Heteroleptic Carbones L1-C-L2.

Angewandte Chemie (International ed. in English)·2026
Same journal

Proton Transfer Shuttle Mediated Dormant-Active Balance for Accelerated and Controlled Polymerization of N-Carboxyanhydrides.

Angewandte Chemie (International ed. in English)·2026
Same journal

Chloride-Regulated Depolymerization of Aluminosilicate Networks for Fast Ion Transport Compliant Interfaces in Sustainable All-Solid-State Sodium Batteries.

Angewandte Chemie (International ed. in English)·2026
Same journal

Asymmetric Zn─N<sub>2</sub>O-Coordinated Hydrogen-Bonded Organic Frameworks for Electrochemical Hydrogen Peroxide Production and Wastewater Purification.

Angewandte Chemie (International ed. in English)·2026
Same journal

Photocatalytic Cascade Nitrogen Fixation for Selective Purification of Methane-Rich Coal-Bed Gas Over a Bimetallic MOF.

Angewandte Chemie (International ed. in English)·2026
Same journal

Scalable Art-Inspired Tessellated Covalent Organic Framework Membranes Enable Highly Selective Ion Separation.

Angewandte Chemie (International ed. in English)·2026
Same journal

Layered Copper-Anthraquinone Coordination Polymer Cathode Leveraging Dual-Redox Sites and Facilitated Ion Diffusion for High-Performance Lithium-Ion Batteries.

Angewandte Chemie (International ed. in English)·2026
See all related articles

Related Experiment Video

Updated: Jan 2, 2026

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
08:56

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions

Published on: November 30, 2022

3.3K

Persistent Borafluorene Radicals.

Wenlong Yang1, Kelsie E Krantz1, Lucas A Freeman1

  • 1Department of Chemistry, University of Virginia, 409 McCormick Rd./ PO Box 400319, Charlottesville, VA, 22904, USA.

Angewandte Chemie (International Ed. in English)
|December 10, 2019
PubMed
Summary
This summary is machine-generated.

Stable crystalline borafluorene radicals stabilized by N-heterocyclic carbene (NHC) and cyclic (alkyl)(amino)carbene (CAAC) ligands were synthesized. Spin density localization on boron atoms and tunable electronic properties were observed, highlighting Lewis base-dependent tuning of these novel radical materials.

Keywords:
borafluorenesboroncarbenesradicals

More Related Videos

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
08:01

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo

Published on: September 26, 2016

9.7K
Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
14:22

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development

Published on: April 15, 2013

20.7K

Related Experiment Videos

Last Updated: Jan 2, 2026

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
08:56

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions

Published on: November 30, 2022

3.3K
Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
08:01

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo

Published on: September 26, 2016

9.7K
Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
14:22

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development

Published on: April 15, 2013

20.7K

Area of Science:

  • Organometallic Chemistry
  • Materials Science
  • Radical Chemistry

Background:

  • N-heterocyclic carbenes (NHCs) and cyclic (alkyl)(amino)carbenes (CAACs) are versatile ligands in stabilizing reactive species.
  • Borafluorenes are organoboron compounds with potential applications in materials science.
  • Stable organic radicals are of interest for their unique electronic and magnetic properties.

Purpose of the Study:

  • To synthesize and characterize novel N-heterocyclic carbene (NHC)- and cyclic (alkyl)(amino)carbene (CAAC)-stabilized borafluorene radicals.
  • To investigate the electronic structure and spin density distribution in these novel radical species.
  • To explore the influence of Lewis base ligands on the properties of borafluorene radicals.

Main Methods:

  • Isolation and characterization using elemental analysis and single-crystal X-ray diffraction.
  • Spectroscopic analysis including UV/Vis absorption and electron paramagnetic resonance (EPR).
  • Electrochemical studies using cyclic voltammetry (CV) and theoretical calculations.

Main Results:

  • Successful isolation and characterization of crystalline NHC- and CAAC-stabilized borafluorene radicals.
  • Significant spin density localized on boron atoms (0.322 for CAAC, 0.369 for NHC).
  • Differential delocalization of unpaired electrons over ligands and borafluorene π-systems depending on the carbene ligand.
  • Remarkable solid-state and solution stability of the synthesized radicals.

Conclusions:

  • The study reports the first crystalline borafluorene radicals stabilized by NHC and CAAC ligands.
  • Lewis base properties of the carbene ligands enable electrostructural tuning of these materials-relevant radicals.
  • The synthesized borafluorene radicals exhibit high stability, suggesting potential for future applications.