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

Aromatic Hydrocarbon Cations: Structural Overview01:18

Aromatic Hydrocarbon Cations: Structural Overview

4.1K
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...
4.1K
Aromatic Hydrocarbon Anions: Structural Overview01:18

Aromatic Hydrocarbon Anions: Structural Overview

4.1K
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...
4.1K
Five-Membered Heterocyclic Aromatic Compounds: Overview01:13

Five-Membered Heterocyclic Aromatic Compounds: Overview

5.9K
Heterocyclic aromatic compounds are cyclic compounds that are aromatic and have one or more heteroatoms—atoms other than carbon, in the ring. Depending upon the number of atoms present in the ring, they can be either five or six-membered. Examples of five-membered heterocyclic aromatic compounds include pyrrole, furan, thiophene, and imidazole. Pyrrole consists of one nitrogen atom having one lone pair of electrons. Furan and thiophene have one oxygen and one sulfur heteroatom,...
5.9K
Frost Circles for Different Conjugated Systems01:18

Frost Circles for Different Conjugated Systems

4.0K
The inscribed polygon method is consistent with Hückel’s 4n + 2 rule and helps to learn whether the given cyclic compound is aromatic or not. The compound is stable and aromatic if every bonding molecular orbital (MO) is completely filled with a pair of electrons. However, if the non-bonding or antibonding orbitals are filled with electrons, the compound is unstable and not aromatic. Consider the Frost circle diagrams for cycloalkenes containing 4 to 8 carbons.
4.0K
Criteria for Aromaticity and the Hückel 4n + 2 Rule01:20

Criteria for Aromaticity and the Hückel 4n + 2 Rule

14.3K
Like benzene, cyclobutadiene and cyclooctatetraene are cyclic compounds with alternate single and double bonds. However, their chemical behavior differs from benzene, as they are unstable and not aromatic. So, what are the structural characteristics of unsaturated compounds categorized as aromatic?  
For the first time, Eric Hückel, a German chemical physicist, derived a set of structural features for a compound to be classified as aromatic. This is now known as Hückel’s rule or the 4n +...
14.3K
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds01:14

π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds

2.0K
In aromatic compounds, such as benzene, the circulation of (4n + 2) π-electrons sets up a diamagnetic or diatropic ring current around the perimeter of the molecule. This current induces a magnetic field that opposes the external field inside the ring and reinforces it on the outside. The protons in benzene are deshielded and exhibit high chemical shifts in the range 6.5–8.5 ppm. The shielding effect at the center of the ring is evident in complex aromatic molecules, such as...
2.0K

You might also read

Related Articles

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

Sort by
Same author

Solid-State 3D Electrochemiluminescence Platform: Depth-Tuned Ru Complexes Positioning for Label-Free High-Resolution Imaging.

ACS omega·2026
Same author

Iterative Synthesis of Pyrene-Coronene Molecular Graphene Nanoribbons.

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

Mapping reaction pathways and catalyst dynamics in electrochemical CO<sub>2</sub> reduction through <i>in situ</i> and <i>operando</i> characterisation.

Chemical communications (Cambridge, England)·2026
Same author

Vaccine uptake in the context of mandate announcement and removal: Evidence from Europe and North America.

Vaccine·2026
Same author

STEM in an SEM: Towards high-throughput imaging and analysis of metal nanoclusters.

Ultramicroscopy·2026
Same author

Direct Imaging Reveals the Atomic Mechanism of Active-Site Formation in Nanoclusters for Hydrogen Production.

Advanced materials (Deerfield Beach, Fla.)·2026

Related Experiment Video

Updated: Mar 6, 2026

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
09:22

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives

Published on: February 7, 2017

8.3K

Twisted Aromatic Frameworks: Readily Exfoliable and Solution-Processable Two-Dimensional Conjugated Microporous

A Belen Marco1, Diego Cortizo-Lacalle1, Iñigo Perez-Miqueo2

  • 1POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018, Donostia-San Sebastian, Spain.

Angewandte Chemie (International Ed. in English)
|March 21, 2017
PubMed
Summary

Researchers created twisted 2D aromatic frameworks using bulky substituents. These distorted structures reduce layer interactions, enabling easier exfoliation and dispersion in solvents.

Keywords:
carbon nanostructuresmaterials sciencenanocarbonsorganic frameworkstwisted aromatic systems

More Related Videos

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
08:42

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Published on: July 10, 2017

14.2K
Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes
09:09

Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes

Published on: December 15, 2015

9.9K

Related Experiment Videos

Last Updated: Mar 6, 2026

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
09:22

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives

Published on: February 7, 2017

8.3K
Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
08:42

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Published on: July 10, 2017

14.2K
Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes
09:09

Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes

Published on: December 15, 2015

9.9K

Area of Science:

  • Materials Science
  • Supramolecular Chemistry

Background:

  • Two-dimensional (2D) aromatic frameworks are crucial in materials science.
  • Controlling interlayer interactions is key for applications like dispersions and coatings.

Purpose of the Study:

  • To synthesize novel twisted 2D aromatic frameworks.
  • To investigate the impact of bulky substituents on framework distortion and interlayer interactions.
  • To assess the exfoliation and dispersion properties of the resulting materials.

Main Methods:

  • Synthesis of 2D aromatic frameworks with sterically demanding substituents at the nodes.
  • Structural characterization using techniques like X-ray diffraction.
  • Evaluation of interlayer interactions through physical property measurements.
  • Assessment of exfoliation and dispersion in various organic solvents.

Main Results:

  • Successfully prepared twisted 2D aromatic frameworks by overcrowding nodes with bulky, rigid substituents.
  • The resulting frameworks exhibit significant distortion with alternating out-of-plane substituents.
  • Diminished interlayer interactions were observed due to the distorted structure.
  • Enhanced exfoliation and dispersion of individual layers in organic media were achieved.

Conclusions:

  • Bulky substituents effectively induce twisting and distortion in 2D aromatic frameworks.
  • Framework distortion significantly weakens interlayer interactions.
  • These twisted frameworks show promise for applications requiring facile layer exfoliation and dispersion.