Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

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

[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.

Aromatic Hydrocarbon Cations: Structural Overview

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...

Aromatic Hydrocarbon Anions: Structural Overview

Aromatic Hydrocarbon Anions: Structural Overview

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 overlap of p...

Thermal Electrocyclic Reactions: Stereochemistry

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.

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation

Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.

You might also read

Related Articles

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

Sort by

Same author

Graphene oxide-polydopamine membranes with controlled interlayer spacing.

Nature·2026

Same author

Robust and well-structured graphene oxide membranes crosslinked by phenylboronic acid for efficient heavy metal ion sieving.

Nanoscale·2026

Same author

Graphdiyne confined-membrane with intrinsic in-plane-pores for angstrom-scale gas sieving.

Nature communications·2026

Same author

Single atom platinum catalyst construction based on graphene defects.

Physical chemistry chemical physics : PCCP·2026

Same author

Highly efficient and ultrafast gaseous iodide removal by controlling the oxidation degree and size of graphene oxide membranes.

Nanoscale·2026

Same author

In-situ revitalizing end-of-life MBR membranes via a curtain-type dynamic membrane process.

Nature communications·2026

Search research articles

Related Experiment Video

Updated: May 23, 2026

Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes

Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes

Published on: August 16, 2018

Highly selective C₂H₄/C₂H₂ separation using a cyano-functionalized alkadiyne-pyrene conjugated framework membrane.

Jie Liu¹, Junjie Chen¹, Guosheng Shi¹

¹Shanghai Key Laboratory of Atomic Control and Application of Inorganic 2D Supermaterials, Shanghai Applied Radiation Institute, Shanghai University, Shanghai, 200444, China. liuxing0215@shu.edu.cn.

Physical Chemistry Chemical Physics : PCCP

|May 22, 2026

Summary

This study developed a novel membrane for efficient separation of ethylene and acetylene gases. The cyano-functionalized membrane utilizes specific interactions to selectively permeate ethylene, achieving high separation performance.

More Related Videos

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

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

Published on: December 15, 2015

Related Experiment Videos

Last Updated: May 23, 2026

Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes

Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes

Published on: August 16, 2018

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

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

Published on: December 15, 2015

Area of Science:

Materials Science
Chemical Engineering
Nanotechnology

Background:

Separating gases like ethylene and acetylene is crucial but challenging due to similar sizes.
Existing methods often lack efficiency and selectivity.

Purpose of the Study:

To design and fabricate a highly selective membrane for ethylene/acetylene separation.
To investigate the role of cyano groups in enhancing separation performance.

Main Methods:

Incorporation of cyano (CN) groups into a poly(1,3,6,8-tetraethynylpyrene) (PTEP) conjugated framework membrane.
Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations.
Experimental measurement of gas permeance and selectivity.

Main Results:

The CN-functionalized membrane exhibited significantly narrowed pores and selective C-H⋯N hydrogen bonding with ethylene.
DFT calculations showed a much lower diffusion barrier for ethylene (0.87 kcal mol⁻¹) than acetylene (6.87 kcal mol⁻¹).
MD simulations revealed a dynamic selectivity of 46.7 ± 4.1 for C₂H₄/C₂H₂ separation, with high permeance values.

Conclusions:

The developed membrane offers a versatile strategy for precise control of pore size and chemical functionality.
This approach enables advanced gas separation performance, surpassing many existing covalent organic framework (COF) membranes.
Provides valuable insights for designing next-generation separation membranes.