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

Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview01:27

Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview

2.1K
Wilhelm Rudolph Fittig discovered the pinacol coupling reaction in 1859. It is a radical dimerization reaction and involves the reductive coupling of aldehydes or ketones in the presence of hydrocarbon solvent to yield vicinal diols.
2.1K
Aryldiazonium Salts to Azo Dyes: Diazo Coupling01:11

Aryldiazonium Salts to Azo Dyes: Diazo Coupling

3.5K
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 para...
3.5K
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction01:22

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

2.2K
The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.
2.2K
Aldehydes and Ketones with HCN: Cyanohydrin Formation Mechanism01:10

Aldehydes and Ketones with HCN: Cyanohydrin Formation Mechanism

4.1K
Cyanohydrins are formed when cyanide nucleophiles and carbonyl compounds like aldehydes and ketones react. A strong base, the cyanide ion, catalyzes cyanohydrin formation. The ions are generated from HCN under aqueous conditions. Once the cyanide ions are generated, the first step involves the nucleophilic attack of the cyanide ions on the electrophilic carbonyl carbon. This attack shifts the π electrons from the C=O to the oxygen atom forming the alkoxide ion intermediate. The alkoxide anion...
4.1K
Aldehydes and Ketones with HCN: Cyanohydrin Formation Overview01:32

Aldehydes and Ketones with HCN: Cyanohydrin Formation Overview

3.7K
Cyanohydrins are compounds that contain –CN and –OH groups on the same carbon atom. They are formed by the nucleophilic addition of the cyanide ions to the carbonyl group. Cyanide ions are highly basic and nucleophilic and can be generated from HCN under aqueous conditions. However, since HCN is a weak acid, the number of cyanide ions generated is very small. Hence, a small amount of base or KCN/NaCN is added to HCN to increase the concentration of the cyanide ions in the reaction...
3.7K
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

2.5K
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
2.5K

You might also read

Related Articles

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

Sort by
Same author

Palladium-Catalyzed Selective Alkylation of 2-Alkynyl Allyl Ethers with Hydrazones <i>via HOME</i>-Chemistry.

Organic letters·2026
Same author

Modular synthesis of trisubstituted olefins and 1,3-dienes from renewable alcohols via ligand-enabled nickel catalysis.

Nature communications·2026
Same author

Precision indole skeletal editing for single-carbon replacement.

Science (New York, N.Y.)·2026
Same author

Ligand-Switched Regiodivergent Fluoroallylic Alkylation of Secondary Nitroalkanes via an Unusual Inner-Sphere Pathway.

Angewandte Chemie (International ed. in English)·2026
Same author

A General Platform for Aryl/Alkyl Radical Functionalization Enabled by Photoinduced Electron Donor-Acceptor Complex.

Organic letters·2026
Same author

HP(O)Ph<sub>2</sub>‑Mediated Hydrodefluorination of Polyfluoro(hetero)arenes.

JACS Au·2026

Related Experiment Video

Updated: Dec 26, 2025

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
10:12

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Published on: April 4, 2014

13.4K

Light-enabled metal-free pinacol coupling by hydrazine.

Zihang Qiu1, Hanh D M Pham1, Jianbin Li1

  • 1Department of Chemistry , FQRNT Centre for Green Chemistry and Catalysis , McGill University , 801 Sherbrooke St. W. , Montreal , Quebec H3A 0B8 , Canada . Email: rustam.khaliullin@mcgill.ca ;

Chemical Science
|March 20, 2020
PubMed
Summary

Researchers developed a metal-free pinacol coupling using light and hydrazine. This sustainable method efficiently forms carbon-carbon bonds, producing only nitrogen and hydrogen gas as byproducts.

More Related Videos

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions
11:44

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

Published on: March 20, 2014

25.8K
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

6.6K

Related Experiment Videos

Last Updated: Dec 26, 2025

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
10:12

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Published on: April 4, 2014

13.4K
Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions
11:44

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

Published on: March 20, 2014

25.8K
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

6.6K

Area of Science:

  • Organic Chemistry
  • Sustainable Chemistry
  • Photochemistry

Background:

  • Efficient carbon-carbon bond formation is crucial in organic synthesis.
  • Traditional pinacol coupling relies on metal reductants, posing sustainability challenges due to waste.
  • A metal-free approach to pinacol coupling is a significant scientific goal.

Purpose of the Study:

  • To develop a novel, metal-free protocol for the pinacol coupling reaction.
  • To utilize a clean, non-metallic reductant for efficient C-C bond formation.
  • To investigate a sustainable alternative to traditional metal-mediated coupling reactions.

Main Methods:

  • A light-driven protocol employing hydrazine (N2H4) as a hydrogen-atom-transfer (HAT) reductant.
  • Metal-free conditions were employed, avoiding the use of active metals.
  • Experimental and computational methods were combined to elucidate the reaction mechanism.

Main Results:

  • Successful demonstration of a light-driven, metal-free pinacol coupling.
  • Hydrazine served as an effective non-metallic reductant, producing only N2 and H2 gases.
  • The reaction exhibited a broad scope for aromatic ketones and good functional group tolerance.

Conclusions:

  • A novel and sustainable metal-free pinacol coupling reaction has been achieved using photoredox catalysis with hydrazine.
  • The reaction proceeds via a hydrogen-atom-transfer (HAT) mechanism, distinct from the single-electron-transfer (SET) pathway typical of metal reductants.
  • This method offers an environmentally friendly alternative for C-C bond formation in organic synthesis.