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

Five-Membered Heterocyclic Aromatic Compounds: Overview01:13

Five-Membered Heterocyclic Aromatic Compounds: Overview

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, respectively.
Aromatic Hydrocarbon Cations: Structural Overview01:18

Aromatic Hydrocarbon Cations: Structural Overview

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 with both...
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction01:16

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
Criteria for Aromaticity and the Hückel 4n + 2 Rule01:20

Criteria for Aromaticity and the Hückel 4n + 2 Rule

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 + 2 rule.
Coordination Number and Geometry02:57

Coordination Number and Geometry

For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
Frost Circles for Different Conjugated Systems01:18

Frost Circles for Different Conjugated Systems

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.

You might also read

Related Articles

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

Sort by
Same author

The Construction of a Microbial Synthesis System for Rare Earth Enrichment and Material Applications.

Advanced materials (Deerfield Beach, Fla.)·2023
Same author

Quantitatively relating magnetic resonance <i>T</i><sub>1</sub> and <i>T</i><sub>2</sub> to glycosaminoglycan and collagen concentrations mediated by penetrated contrast agents and biomacromolecule-bound water.

Regenerative biomaterials·2023
Same author

ROS Generative Black Phosphorus-Tamoxifen Nanosheets for Targeted Endocrine-Sonodynamic Synergistic Breast Cancer Therapy.

International journal of nanomedicine·2023
Same author

Single-Atom Rh on High-Index CeO<sub>2</sub> Facet for Highly Enhanced Catalytic CO Oxidation.

Angewandte Chemie (International ed. in English)·2023
Same author

New Strategy: Molten Salt-Assisted Synthesis to Enhance Lanthanide Upconversion Luminescence.

Small (Weinheim an der Bergstrasse, Germany)·2023
Same author

Facile synthesis of Sb<sup>3+</sup>-doped (Bmim)<sub>2</sub>InCl<sub>5</sub>(H<sub>2</sub>O) through a grinding method for light-emitting diodes.

Dalton transactions (Cambridge, England : 2003)·2023

Related Experiment Video

Updated: Jun 4, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
09:35

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

Mn4-hinged bithiacalix[4]arenes accommodating fullerenes.

Yanfeng Bi1, Wuping Liao, Xiaofei Wang

  • 1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.

Dalton Transactions (Cambridge, England : 2003)
|February 2, 2011
PubMed
Summary
This summary is machine-generated.

Calixarene-manganese-calixarene dumbbell structures adapt to various fullerenes. Fullerene integration significantly alters the packing arrangement of these molecular units.

More Related Videos

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
10:44

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
19:58

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Published on: July 30, 2017

Related Experiment Videos

Last Updated: Jun 4, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
09:35

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

Published on: September 18, 2016

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
10:44

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
19:58

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Published on: July 30, 2017

Area of Science:

  • Supramolecular Chemistry
  • Materials Science

Background:

  • Calixarenes are versatile macrocyclic compounds with tunable properties.
  • Fullerenes are spherical carbon molecules with unique electronic characteristics.
  • Molecular self-assembly is crucial for designing advanced materials.

Purpose of the Study:

  • To investigate the interaction between calixarene-manganese-calixarene dumbbell units and fullerenes.
  • To explore how fullerene inclusion affects the supramolecular packing of dumbbell structures.
  • To assess the adaptability of calixarene frameworks for accommodating guest molecules.

Main Methods:

  • Synthesis of calixarene-Mn(4)-calixarene dumbbell-like units.
  • Co-crystallization experiments with various fullerenes (e.g., C60, C70).
  • Single-crystal X-ray diffraction analysis to determine packing structures.

Main Results:

  • The dumbbell units exhibit flexible curved surfaces capable of accommodating different fullerenes.
  • The inclusion of fullerenes leads to a complete remodeling of the dumbbell unit packing.
  • Specific fullerene guests induce distinct packing motifs within the crystal lattice.

Conclusions:

  • Calixarene-based molecular architectures can be designed to incorporate and adapt to guest molecules like fullerenes.
  • Fullerene integration offers a strategy to control and modify the solid-state assembly of supramolecular structures.
  • This work demonstrates the potential of functionalized calixarenes in host-guest chemistry and crystal engineering.