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

Stability of Substituted Cyclohexanes02:30

Stability of Substituted Cyclohexanes

This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
Disubstituted Cyclohexanes: cis-trans Isomerism02:37

Disubstituted Cyclohexanes: cis-trans Isomerism

Depending upon the different spatial orientation of the substituents, the disubstituted cycloalkanes exhibit two types of stereoisomers. The cis isomers have the substituents on the same side of the ring, whereas the trans isomers have the substituents on the opposite sides. These stereoisomers exhibit different physical properties and cannot be interconverted without breaking the carbon-carbon bonds.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
Thermal Electrocyclic Reactions: Stereochemistry01:17

Thermal Electrocyclic Reactions: Stereochemistry

The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Thermal and Photochemical Electrocyclic Reactions: Overview01:26

Thermal and Photochemical Electrocyclic Reactions: Overview

Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
Conformations of Cycloalkanes02:29

Conformations of Cycloalkanes

Adolf von Baeyer attempted to explain the instabilities of small and large cycloalkane rings using the concept of angle strain — the strain caused by the deviation of bond angles from the ideal 109.5° tetrahedral value for sp3  hybridized carbons. However, while cyclopropane and cyclobutane are strained, as expected from their highly compressed bond angles, cyclopentane is more strained than predicted, and cyclohexane is virtually strain-free. Hence, Baeyer’s theory that was based on the...
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...

You might also read

Related Articles

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

Sort by
Same author

Neighbouring group participation hindered by force as a molecular design for covalent catch bonds.

Nature communications·2026
Same author

Dynamics and charge transport in PVDF-HFP/protic ionic liquid (PIL) membranes: The effect of PIL concentration.

The Journal of chemical physics·2026
Same author

A Practical User Guide to Stress Relaxation Spectra of Dynamic Covalent Networks.

ACS polymers Au·2026
Same author

Comparing Triaminononane and TREN as Trifunctional Amine Cross-Linkers in Covalent Adaptable Networks.

ACS polymers Au·2025
Same author

Anion Engineering of Ionic Liquid-Based Polymer Electrolytes for Interfacial Stabilization in Lithium Metal Batteries.

The journal of physical chemistry letters·2025
Same author

Enhanced decoupling of conductivity relaxation from structural relaxation in non-stoichiometric protic ionic liquids involving triflic acid and 2-aminoethyl hydrogen sulfate.

The Journal of chemical physics·2024

Related Experiment Video

Updated: Jun 19, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
06:24

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal

Published on: October 31, 2019

Thermotropic phase behavior of trialkyl cyclohexanetriamides.

Itsuro Tomatsu1, Carel F C Fitié, Dmytro Byelov

  • 1Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.

The Journal of Physical Chemistry. B
|October 23, 2009
PubMed
Summary

Symmetric cyclohexanetriamides with linear alkyl chains form plastic columnar and nematic liquid crystalline phases. Branched alkyl chains also induce columnar phases, with potential for responsive materials.

More Related Videos

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
06:26

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets

Published on: May 15, 2017

Preparation of Carbon Nanosheets at Room Temperature
10:44

Preparation of Carbon Nanosheets at Room Temperature

Published on: March 8, 2016

Related Experiment Videos

Last Updated: Jun 19, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
06:24

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal

Published on: October 31, 2019

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
06:26

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets

Published on: May 15, 2017

Preparation of Carbon Nanosheets at Room Temperature
10:44

Preparation of Carbon Nanosheets at Room Temperature

Published on: March 8, 2016

Area of Science:

  • Materials Science
  • Supramolecular Chemistry
  • Physical Chemistry

Background:

  • Understanding the thermotropic phase behavior of molecules is crucial for designing advanced materials.
  • Cyclohexanetriamides are a class of molecules with potential for self-assembly into ordered structures.
  • The influence of alkyl chain structure (linear vs. branched) on mesophase formation is not fully understood.

Purpose of the Study:

  • To investigate the thermotropic phase behavior of symmetric cyclohexanetriamides with varying linear and branched alkyl chains.
  • To correlate molecular structure with the formation of specific liquid crystalline phases.
  • To explore the potential of these molecules in responsive materials.

Main Methods:

  • Calorimetry (DSC) for thermal transitions.
  • Microscopy (Polarized Light Microscopy) for phase identification.
  • Solid-state Nuclear Magnetic Resonance (NMR) for structural analysis.
  • Dielectric Relaxation Spectroscopy (DRS) for dynamic properties.
  • X-ray Scattering (XRD) for lattice structure determination.

Main Results:

  • Linear alkyl chains (C6+) induced columnar plastic phases with pseudocentered rectangular lattices.
  • Nematic liquid crystalline phases were observed for cyclohexanetriamides with C8+ linear alkyl chains.
  • Branched octyl chains generally formed columnar phases with rectangular lattices, with an exception for highly branched groups.
  • Less symmetrical columnar phases were attributed to non-cylindrical column stacking.
  • Dielectric relaxation spectra indicated cooperative reorientation of macrodipolar columns, suggesting responsiveness.

Conclusions:

  • The length and branching of alkyl chains significantly dictate the thermotropic phase behavior of cyclohexanetriamides.
  • These molecules can form ordered columnar and nematic liquid crystalline phases.
  • The observed properties highlight the potential of cyclohexanetriamides as building blocks for responsive functional materials.