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

Aryldiazonium Salts to Azo Dyes: Diazo Coupling01:11

Aryldiazonium Salts to Azo Dyes: Diazo Coupling

3.5K
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para...
3.5K
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
Radicals: Electronic Structure and Geometry01:07

Radicals: Electronic Structure and Geometry

4.8K
This lesson delves into the geometry of a radical, which is influenced by the electronic structure of the molecule. The principle is similar to that of a lone pair, where the unpaired electron influences the geometry at the radical center.
Accordingly, the structure of a trivalent radical lies between the geometries of carbocations and carbanions. An sp2-hybridized carbocation is trigonal planar, while an sp3-hybridized carbanion is trigonal pyramidal. Here, the difference in geometry is...
4.8K
Nomenclature of Aryl and Heterocyclic Amines01:10

Nomenclature of Aryl and Heterocyclic Amines

3.0K
The simplest aromatic amine is phenylamine, which contains an –NH2 functionality directly attached to an aromatic ring. The name aniline is designated for this skeleton. As shown in Figure 1, the common names of the functionalized anilines involve prefixes ortho-, meta-, and para- to indicate the substitution position. Different functionalized aniline derivatives also have notable trivial names.
3.0K
Aromatic Hydrocarbon Anions: Structural Overview01:18

Aromatic Hydrocarbon Anions: Structural Overview

3.4K
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous...
3.4K
Aromatic Hydrocarbon Cations: Structural Overview01:18

Aromatic Hydrocarbon Cations: Structural Overview

3.6K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
3.6K

You might also read

Related Articles

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

Sort by
Same author

SITH: A quantum-chemical framework for predicting bond destabilization in stretched molecules.

The Journal of chemical physics·2026
Same author

A Chiral Saddle-Shaped Nanographene With Two Heptagon-Embedded [4]Helicenes.

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

An efficient and exact reformulation of fourth-order algebraic diagrammatic construction schemes.

The Journal of chemical physics·2026
Same author

Molecular Mechanism of the Oxidative Cleavage of Alkenes by Photoexcited Nitroarenes.

Journal of the American Chemical Society·2026
Same author

RE-ADC: The algebraic diagrammatic construction scheme for the polarization propagator using the retaining-the-excitation-degree partitioning.

The Journal of chemical physics·2026
Same author

Mixed-order schemes for molecular properties employing ADC/ISR.

The Journal of chemical physics·2026

Related Experiment Video

Updated: Dec 26, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
11:45

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

Published on: August 22, 2018

8.7K

Quinoidal Azaacenes: 99 % Diradical Character.

Sebastian N Intorp1, Manuel Hodecker2, Matthias Müller1

  • 1Organisch-Chemisches Institut, Ruprecht-Karls-Universität, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.

Angewandte Chemie (International Ed. in English)
|March 20, 2020
PubMed
Summary

New quinoidal azaacenes with high diradical character were synthesized. These compounds show paramagnetic behavior and stable triplet states, offering potential for advanced material applications.

Keywords:
acenesheteroaromaticsradicalsstructure elucidationsynthetic methods

More Related Videos

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
07:12

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

6.6K
Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
04:38

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions

Published on: July 28, 2022

3.3K

Related Experiment Videos

Last Updated: Dec 26, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
11:45

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

Published on: August 22, 2018

8.7K
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
07:12

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

6.6K
Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
04:38

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions

Published on: July 28, 2022

3.3K

Area of Science:

  • Organic Chemistry
  • Materials Science

Background:

  • Diradical compounds are of interest for their unique electronic properties.
  • Azaacenes are nitrogen-containing polycyclic aromatic hydrocarbons with potential applications in organic electronics.

Purpose of the Study:

  • To synthesize novel quinoidal azaacenes with significant diradical character.
  • To investigate the electronic and magnetic properties of these novel compounds.

Main Methods:

  • Synthesis of quinoidal azaacenes.
  • Electron paramagnetic resonance (EPR) and Nuclear Magnetic Resonance (NMR) spectroscopy.
  • SQUID magnetometry.

Main Results:

  • Synthesis of compounds with diradical character (y=0.95 to 0.99).
  • Observation of paramagnetic behavior and thermally populated triplet states.
  • Extremely low energy gap (ΔEST') between singlet and triplet states (0.58–1.0 kcal mol-1).
  • High stability in solution (half-life ≈14–21 h) and solid state (weeks).

Conclusions:

  • The synthesized quinoidal azaacenes possess near-pure diradical character.
  • These compounds exhibit unique magnetic properties due to low-lying triplet states.
  • Their stability suggests potential for use in organic electronics and spintronics.