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

Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN101:14

Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1

2.3K
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
2.3K
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions01:20

Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions

2.1K
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
2.1K
Diazonium Group Substitution: –OH and –H01:19

Diazonium Group Substitution: –OH and –H

3.0K
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
3.0K
Aryldiazonium Salts to Azo Dyes: Diazo Coupling01:11

Aryldiazonium Salts to Azo Dyes: Diazo Coupling

3.2K
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...
3.2K
Aromatic Hydrocarbon Anions: Structural Overview01:18

Aromatic Hydrocarbon Anions: Structural Overview

3.2K
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...
3.2K
Diels–Alder Reaction: Characteristics of Dienes01:29

Diels–Alder Reaction: Characteristics of Dienes

4.6K
The Diels–Alder reaction brings together a diene and a dienophile to form a six-membered ring. Both components have unique characteristics that influence the rate of the reaction.
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is...
4.6K

You might also read

Related Articles

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

Sort by
Same author

Symmetry-breaking charge separation: from charge generation to functional charge utilization.

Chemical science·2026
Same author

Covalent Organic Framework Photocatalysts: Decoding Linkage Chemistry in Hydrogen Peroxide Synthesis From Air and Water.

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

Bending-Induced Vibrational Landscape Reorganization Governs Energy Dissipation in Perylene Bisimides.

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

Direct Construction of Magnetic and Electrical Two-Dimensional Radical Covalent Organic Frameworks.

Nature communications·2026
Same author

Redox- and protonation-driven Baird and Clar aromaticity in asymmetric multicyclic octaphyrins.

Chemical science·2026
Same author

Inner-Bond Cleavage of Sterically Congested Dibenzo[<i>g</i>,<i>p</i>]chrysene to a Rigid Figure-Eight Macrocycle.

Organic letters·2026

Related Experiment Video

Updated: Oct 27, 2025

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
07:30

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

8.3K

Antiaromatic 1,5-Diaza-s-indacenes.

Kensuke Hanida1, Jinseok Kim2, Norihito Fukui1

  • 1Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Japan.

Angewandte Chemie (International Ed. in English)
|July 21, 2021
PubMed
Summary

Researchers synthesized nitrogen-doped s-indacene analogues, 1,5-diaza-s-indacenes. These compounds display antiaromaticity and enhanced electron-accepting properties compared to the parent hydrocarbon.

Keywords:
NIR absorptionantiaromaticityconjugationnitrogen heterocycless-indacene

More Related Videos

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
11:04

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

Published on: June 13, 2022

3.2K
Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities
09:10

Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities

Published on: May 27, 2015

6.8K

Related Experiment Videos

Last Updated: Oct 27, 2025

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
07:30

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

Published on: January 21, 2020

8.3K
Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
11:04

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine

Published on: June 13, 2022

3.2K
Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities
09:10

Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities

Published on: May 27, 2015

6.8K

Area of Science:

  • Organic Chemistry
  • Materials Science
  • Supramolecular Chemistry

Background:

  • s-Indacene is a non-alternant hydrocarbon with 12 π-electrons in a cyclic π-conjugation system.
  • Nitrogen-doped analogues offer potential for novel electronic and optical properties.

Purpose of the Study:

  • To synthesize and characterize 1,5-diaza-s-indacene, a nitrogen-doped analogue of s-indacene.
  • To investigate the antiaromaticity and electronic properties of the novel compounds.
  • To explore the tunability of their optical and redox characteristics.

Main Methods:

  • Two-step synthesis involving palladium-catalyzed Larock cyclization.
  • Hydrogen abstraction for final product formation.
  • Spectroscopic and computational analyses to confirm structure and properties.

Main Results:

  • Successful synthesis of 1,5-diaza-s-indacenes from 2,5-dichlorobenzene-1,4-diamine.
  • Demonstrated distinct antiaromaticity, evidenced by bond-length alternation and a forbidden HOMO-LUMO transition.
  • Observed enhanced electron-accepting ability due to imine-type nitrogen atoms.
  • Showcased effective conjugation for tuning absorption spectra and redox properties.

Conclusions:

  • 1,5-Diaza-s-indacenes represent a novel class of antiaromatic, nitrogen-doped hydrocarbons.
  • These compounds exhibit tunable electronic and optical properties, making them promising for materials applications.
  • The study provides insights into the structure-property relationships of antiaromatic systems.