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

Multiple Halogenation of Methyl Ketones: Haloform Reaction01:28

Multiple Halogenation of Methyl Ketones: Haloform Reaction

A method involving the transformation of methyl ketones to carboxylic acids using excess base and halogen is called the haloform reaction. It begins with the deprotonation of α hydrogen to form an enolate ion which reacts with the electrophilic halogen to give an α-halo ketone. The step continues until all the α protons are substituted to form a trihalomethyl ketone. The resulting molecule is unstable, and in the presence of a hydroxide base, it readily undergoes nucleophilic acyl substitution.
Carboxylic Acids to Methylesters: Alkylation using Diazomethane01:33

Carboxylic Acids to Methylesters: Alkylation using Diazomethane

Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.
Acid-Catalyzed α-Halogenation of Aldehydes and Ketones01:21

Acid-Catalyzed α-Halogenation of Aldehydes and Ketones

By replacing an α-hydrogen with a halogen, acid-catalyzed α-halogenation of aldehydes or ketones yields a monohalogenated product
In the first step of the mechanism, the acid protonates the carbonyl oxygen resulting in a resonance-stabilized cation, which subsequently loses an α-hydrogen to form an enol tautomer. The C=C bond in an enol is highly nucleophilic because of the electron-donating nature of the –OH group. Consequently, the double bond attacks an electrophilic halogen to form a...
IUPAC Nomenclature of Ketones01:09

IUPAC Nomenclature of Ketones

Like aldehydes, ketones are named using IUPAC rules; in this case, by replacing “e” in the name of the longest hydrocarbon chain with “one.” In acyclic ketones, the ketonic carbon is given the lowest locant value. For instance, as shown below, a simple five-carbon ketone is named pentan-2-one, instead of pentan-4-one. IUPAC rules also allow the placing of the locant value before the parent name to give an alternate name, 2-pentanone.
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction01:22

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

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.
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation02:47

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.

You might also read

Related Articles

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

Sort by
Same author

Bioaugmentation in treatment wetlands: Opportunities, challenges, and safety considerations.

Bioresource technology·2026
Same author

The Dual Roles of Innate Lymphoid Cells in Antibacterial Defense and Bacterial Immune Evasion.

Clinical reviews in allergy & immunology·2026
Same author

Mechanistic insights into polylactic acid and cadmium co-regulation of nitrogen dynamics in the pea-soil system via microbial drivers.

Journal of hazardous materials·2026
Same author

Nutrition literacy, dietary diversity, and frailty among older adults in China.

BMC geriatrics·2026
Same author

Microbial Dehalogenation of 3,5,6-Trichlorooctafluorohexanoic Acid under Different Reducing Conditions.

Environmental science & technology·2026
Same author

Plant litter facilitates biotic and abiotic removal of benzo[a]pyrene in iron-based constructed wetlands.

Bioresource technology·2026

Related Experiment Video

Updated: May 19, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
07:06

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

Published on: February 16, 2020

New methylene homologation method for cyclic ketones.

Huaqing Liu1, Chunrui Sun, Nam-Kyu Lee

  • 1Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607, USA.

Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 16, 2012
PubMed
Summary

A novel single-step methylene homologation method was developed by intercepting ketone adducts. Silica gel proved most effective for protonation and ring expansion, enabling this Tiffeneau-Demjanov type reaction.

More Related Videos

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
08:12

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Published on: August 16, 2018

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
07:50

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides

Published on: May 26, 2019

Related Experiment Videos

Last Updated: May 19, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
07:06

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

Published on: February 16, 2020

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
08:12

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species

Published on: August 16, 2018

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
07:50

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides

Published on: May 26, 2019

Area of Science:

  • Organic Chemistry
  • Synthetic Methodology

Background:

  • The Tiffeneau-Demjanov reaction is a classical method for ring expansion.
  • Traditional methods often involve multiple steps and harsh reagents.

Purpose of the Study:

  • To develop a novel, single-step Tiffeneau-Demjanov type methylene homologation.
  • To identify efficient reagents for intermediate protonation and ring expansion.

Main Methods:

  • Reaction of ketones with lithium trimethylsilyldiazomethane to form intermediates.
  • Investigation of various proton sources and Lewis acids for promoting ring expansion.
  • Utilizing silica gel as a catalytic agent.

Main Results:

  • Successfully achieved a one-step methylene homologation of ketones.
  • Silica gel demonstrated superior efficacy as a proton source and catalyst compared to other reagents.
  • The reaction proceeds via interception of specific adducts.

Conclusions:

  • A new, efficient, and single-step Tiffeneau-Demjanov type methylene homologation has been established.
  • Silica gel is an effective and mild reagent for this transformation.
  • This method offers a streamlined approach to ring expansion in organic synthesis.