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

Halogens03:01

Halogens

Group 17 elements, known as halogens, are nonmetals. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine a solid. Astatine is a highly unstable radioactive element, so currently, most of its properties are unknown due to its short half-life. Tennessine is a synthetic element also predicted to be in this group.
Halogenation of Alkenes02:46

Halogenation of Alkenes

Halogenation is the addition of chlorine or bromine across the double bond in an alkene to yield a vicinal dihalide. The reaction occurs in the presence of inert and non-nucleophilic solvents, such as methylene chloride, chloroform, or carbon tetrachloride.
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
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.
Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene01:15

Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene

Chlorination and bromination are important classes of electrophilic aromatic substitutions, where benzene reacts with chlorine or bromine in the presence of a Lewis acid catalyst to give halogenated substitution products. A Lewis acid such as aluminium chloride or ferric chloride catalyzes the chlorination, and ferric bromide catalyzes the bromination reactions. During the bromination of alkenes, bromine polarizes and becomes electrophilic. However, in the bromination of benzene, the bromine...
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene01:13

Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene

Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
Radical Substitution: Halogenation of Alkanes and Alkyl Substituents01:27

Radical Substitution: Halogenation of Alkanes and Alkyl Substituents

In the presence of heat or light, alkanes react with molecular halogens to form alkyl halides by a substitution reaction called radical halogenation. This reaction has three steps: initiation, propagation, and termination, as seen in the radical chlorination of methane to produce methyl chloride.
In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...

You might also read

Related Articles

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

Sort by
Same author

A reactive transport model designed to predict the environmental footprint of an 'in-situ recovery' uranium exploitation.

Journal of contaminant hydrology·2023
Same author

Locomotion of Ants Walking up Slippery Slopes of Granular Materials.

Integrative organismal biology (Oxford, England)·2021
Same author

VZV meningoencephalitis treated with ganciclovir.

Medecine et maladies infectieuses·2020
Same author

An instrument for studying granular media in low-gravity environment.

The Review of scientific instruments·2018
Same author

Temperature, geometry, and bifurcations in the numerical modeling of the cardiac mechano-electric feedback.

Chaos (Woodbury, N.Y.)·2017
Same author

Improved slow magnetic relaxation in optically pure helicene-based Dy<sup>III</sup> single molecule magnets.

Chemical communications (Cambridge, England)·2016

Related Experiment Video

Updated: Jul 14, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
08:43

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Published on: January 19, 2016

The bromochlorofluoromethane saga.

J Crassous1, A Collet

  • 1Stéréochimie et Interactions Moléculaires (UMR ENS-CNRS 5532), Ecole Normale Supérieure de Lyon, 69364 Lyon, France. jeanne.crassous@ens-lyon.fr

Enantiomer
|January 6, 2001
PubMed
Summary

Optically active bromochlorofluoromethane (CHFClBr) was synthesized and its configuration confirmed. The study also performed the first parity violation test on CHFClBr, establishing an upper bound for this stereophysical effect.

Area of Science:

  • Stereochemistry
  • Chiral molecules
  • Parity violation

Background:

  • Optically active haloforms are crucial for fundamental chemical research.
  • Establishing absolute configurations of chiral molecules requires advanced techniques.
  • Parity violation is a subtle quantum mechanical effect with implications in stereochemistry.

Purpose of the Study:

  • To synthesize optically active bromochlorofluoromethane (CHFClBr).
  • To determine the absolute configuration of CHFClBr using spectroscopic and computational methods.
  • To conduct the first parity violation (PV) test on CHFClBr.

Main Methods:

  • Fractional crystallization of strychnine salts for chiral acid separation.
  • X-ray crystallography for absolute configuration determination of the precursor acid.

More Related Videos

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
06:44

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

Published on: March 24, 2018

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations
13:09

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

Published on: January 4, 2018

Related Experiment Videos

Last Updated: Jul 14, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
08:43

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Published on: January 19, 2016

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
06:44

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

Published on: March 24, 2018

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations
13:09

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

Published on: January 4, 2018

  • Raman Optical Activity (ROA) and molecular modeling for haloform configuration assignment.

    • Main Results:

    • Successful synthesis of optically active CHFClBr.
    • Established the absolute configuration of CHFClBr through ROA and molecular modeling.
    • Decarboxylation reaction proceeded with retention of configuration.
    • An upper bound for the parity violation effect in CHFClBr was determined.

    Conclusions:

    • The study provides a reliable method for synthesizing enantiomerically pure CHFClBr.
    • The absolute configuration of CHFClBr was unequivocally assigned.
    • The first PV test on CHFClBr offers insights into stereophysical effects and fundamental physics.