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

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)

1.1K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.1K
Newman Projections02:06

Newman Projections

17.1K
Different notations are used to represent the three-dimensional structure of molecules on two-dimensional surfaces. One of the most commonly used representations is the dash-wedge formula. The dashed wedges, solid wedges, and the plane lines indicate the groups situated behind the plane, coming out of the plane, and in the plane, respectively.
The organic molecules rotate across the single bonds leading to numerous temporary three-dimensional structures of varying energy known as...
17.1K
SN2 Reaction: Stereochemistry02:23

SN2 Reaction: Stereochemistry

9.7K
In an SN2 reaction, the nucleophilic attack on the substrate and departure of the leaving group occurs simultaneously through a transition state. As the nucleophile approaches the substrate from the back-side, the configuration of the substrate carbon changes from tetrahedral to trigonal bipyramidal and then back to tetrahedral, leading to an inversion in the configuration of the product.
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not...
9.7K
Thermal Electrocyclic Reactions: Stereochemistry01:17

Thermal Electrocyclic Reactions: Stereochemistry

2.1K
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.
2.1K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)

1.1K
Vicinal or three-bond coupling is commonly observed between protons attached to adjacent carbons. Here, nuclear spin information is primarily transferred via electron spin interactions between adjacent C‑H bond orbitals. This generally favors the antiparallel arrangement of spins, so 3J values are usually positive.
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the...
1.1K
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement01:21

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement

2.8K
The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.
2.8K

You might also read

Related Articles

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

Sort by
Same author

<i>Ordo ab Chao</i>: Crystallographic Disorder as a Window into Ionic Liquid Structure.

Crystal growth & design·2026
Same author

From Dead Ends to Catalyst Reservoirs: Bimetallic Reactivation of Homoleptic Nickel Pincer Complexes.

Inorganic chemistry·2026
Same author

Acid-Catalyzed Dehydrocoupling of Phosphines.

Inorganic chemistry·2026
Same author

N-N Coupling of Nitrosyl Ligands in a Dinitrosyl Iron Complex Mediated by Exogenous Acids.

Inorganic chemistry·2026
Same author

Amidophenolate Lanthanide Complexes and Their Multielectron Reactivity.

Inorganic chemistry·2026
Same author

Stabilizing Structural Transitional States between 1- and 2-Dimensional Topologies via Hydrogen Bond-Mediated Crystal Engineering.

Journal of the American Chemical Society·2026

Related Experiment Video

Updated: Aug 4, 2025

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
11:44

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

18.0K

Dinickel-Catalyzed N═N Bond Rotation.

Christopher J Rybak1, John M Andjaba1, Chengyi Fan1

  • 1Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States.

Inorganic Chemistry
|April 5, 2023
PubMed
Summary

Dinickel catalysts enable cis/trans isomerization in azoarene molecular switches by facilitating N═N bond rotation. This breakthrough offers a new method for controlling these versatile chemical switches.

More Related Videos

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
05:48

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes

Published on: November 21, 2017

8.1K
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
10:52

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

2.8K

Related Experiment Videos

Last Updated: Aug 4, 2025

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
11:44

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

18.0K
Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
05:48

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes

Published on: November 21, 2017

8.1K
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
10:52

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

2.8K

Area of Science:

  • Organometallic Chemistry
  • Materials Science
  • Supramolecular Chemistry

Background:

  • Azoarenes are stimuli-responsive molecules with a cis/trans isomerization capability.
  • Current methods for azoarene isomerization often rely on external energy inputs like light or heat.

Purpose of the Study:

  • To investigate the catalytic activity of a dinickel complex in promoting azoarene cis/trans isomerization.
  • To elucidate the mechanism of isomerization, focusing on N═N bond rotation.

Main Methods:

  • Synthesis and characterization of a dinickel catalyst.
  • Spectroscopic and crystallographic analysis of catalytic intermediates.
  • Testing the catalyst's efficacy with various acyclic, cyclic, and polymeric azoarenes.

Main Results:

  • A dinickel catalyst was shown to effectively induce cis/trans isomerization in azoarenes.
  • The mechanism involves N═N bond rotation facilitated by the dinickel active site.
  • π-back-bonding interactions in catalytic intermediates were identified as crucial for accelerating bond rotation.
  • The catalytic system demonstrated broad applicability across different azoarene structures.

Conclusions:

  • Dinickel catalysis provides a novel pathway for controlling azoarene isomerization.
  • This catalytic approach offers an alternative to traditional light- or heat-induced switching.
  • The findings expand the utility of azoarene-based molecular switches in various applications.