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

Cycloaddition Reactions: MO Requirements for Photochemical Activation01:12

Cycloaddition Reactions: MO Requirements for Photochemical Activation

2.0K
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
2.0K
Photochemical Electrocyclic Reactions: Stereochemistry01:26

Photochemical Electrocyclic Reactions: Stereochemistry

1.8K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
1.8K
Aryldiazonium Salts to Azo Dyes: Diazo Coupling01:11

Aryldiazonium Salts to Azo Dyes: Diazo Coupling

2.9K
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the...
2.9K
Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism01:18

Benzene to 1,4-Cyclohexadiene: Birch Reduction Mechanism

2.2K
Birch reduction uses solvated electrons as reducing agents. The reaction converts benzene to 1,4-cyclohexadiene. The reaction proceeds by the transfer of a single electron to the ring to form a benzene radical anion. This anion is highly basic—it abstracts a proton from the alcohol to form a cyclohexadienyl radical. Another single electron transfer gives the cyclohexadienyl anion. A proton transfer from the alcohol forms 1,4-cyclohexadiene. Since this reduction occurs via radical anion...
2.2K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation02:17

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

3.3K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.3K
Colors and Magnetism03:02

Colors and Magnetism

11.6K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
11.6K

You might also read

Related Articles

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

Sort by
Same author

Robust Hydrogen-Bonded Organic Framework for pH-Responsive Drug Delivery.

Biomacromolecules·2025
Same author

Targeting Replication Fork Processing Synergizes with PARP Inhibition to Potentiate Lethality in Homologous Recombination Proficient Ovarian Cancers.

Advanced science (Weinheim, Baden-Wurttemberg, Germany)·2025
Same author

Advanced AIE Materials for Environmental Monitoring: Selective Sensing of Thorium(IV) in Aquatic Systems.

ACS applied materials & interfaces·2024
Same author

Addressing the Challenge of a Simultaneous Destructive Assay of Plutonium and Uranium: Highly Precise, Robust, Universal, and Reagent-Free Differential Pulse Voltametric Method Development in Biodegradable Methanesulfonic Acid Medium.

Analytical chemistry·2024
Same author

A BODIPY-Naphtholimine-BF<sub>2</sub> Dyad for Precision Photodynamic Therapy, Targeting, and Dual Imaging of Endoplasmic Reticulum and Lipid Droplets in Cancer.

JACS Au·2024
Same author

Theoretical prediction of donor-acceptor type novel complexes with strong noble gas-boron covalent bond.

Physical chemistry chemical physics : PCCP·2024

Related Experiment Video

Updated: Jun 14, 2025

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
09:12

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Published on: May 21, 2019

9.2K

Azobenzene-Attached (NHC)Gold(I) and (NHC)Copper(I) Complexes as Photoswitchable Catalysts.

Aminul Islam Sk1, Ayan Ghosh2, Kshama Kundu3

  • 1Department of Oils, Oleochemicals and Surfactants Technology, Institute of Chemical Technology, N. P. Marg, Matunga, Mumbai, 400019, India.

Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 4, 2024
PubMed
Summary

This study introduces photoswitchable gold and copper complexes that control reaction rates using light. Light exposure reversibly alters catalytic activity, enabling remote control over chemical reactions.

Keywords:
AzobenzenePhotochromic (NHC)gold(I) complexPhotoswitchable (NHC)copper(I) complexPhotoswitchable catalystRate-controlled reaction

More Related Videos

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

9.6K
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
07:12

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

6.2K

Related Experiment Videos

Last Updated: Jun 14, 2025

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
09:12

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Published on: May 21, 2019

9.2K
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

9.6K
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
07:12

Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions

Published on: July 17, 2020

6.2K

Area of Science:

  • Organometallic Chemistry
  • Photochemistry
  • Catalysis

Background:

  • N-heterocyclic carbenes (NHCs) are crucial ligands in organometallic chemistry.
  • Photoswitchable molecules offer external control over chemical and physical properties.
  • Developing catalysts with tunable activity is essential for advanced chemical synthesis.

Purpose of the Study:

  • To synthesize and characterize novel photoswitchable N-heterocyclic carbene (NHC)-gold(I) and NHC-copper(I) complexes.
  • To investigate the impact of light-induced isomerization on catalytic activity.
  • To demonstrate remote, reversible control over reaction rates using external light stimuli.

Main Methods:

  • Synthesis of N,N'-bis-azobenzene-based NHC-Au(I) and NHC-Cu(I) complexes.
  • Characterization using X-ray diffraction and 1H-NMR spectroscopy.
  • Evaluation of catalytic activity in oxazoline formation and azide-alkyne cycloaddition reactions.
  • UV-visible spectroscopy for photoswitching and recyclability studies.

Main Results:

  • Trans to cis isomerization of azobenzene moieties in Au(I) complexes decreased oxazoline formation rates four-fold.
  • Copper(I) catalyzed azide-alkyne cycloaddition rates were reduced by at least three-fold.
  • Catalytic activity was reversibly modulated by alternating UV and blue light exposure.
  • The catalytic activity of stable trans-trans isomers matched conventional NHC-Au/Cu(I) complexes.

Conclusions:

  • Photoswitchable NHC-Au(I) and NHC-Cu(I) complexes enable light-controlled catalysis.
  • Isomerization of azobenzene ligands provides a mechanism for modulating catalytic rates.
  • These systems offer a promising platform for remote, reversible control in chemical reactions.