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: Overview01:16

Cycloaddition Reactions: Overview

Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
Cycloaddition Reactions: MO Requirements for Thermal Activation01:16

Cycloaddition Reactions: MO Requirements for Thermal Activation

Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
Cycloaddition Reactions: MO Requirements for Photochemical Activation01:12

Cycloaddition Reactions: MO Requirements for Photochemical Activation

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.
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction01:16

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
Hybridization of Atomic Orbitals II03:35

Hybridization of Atomic Orbitals II

sp3d and sp3d 2 Hybridization
Electrophilic 1,2- and 1,4-Addition of X2 to 1,3-Butadiene01:14

Electrophilic 1,2- and 1,4-Addition of X2 to 1,3-Butadiene

Electrophilic addition of halogens to alkenes proceeds via a cyclic halonium ion to form a 1,2-dihalide or a vicinal dihalide.

You might also read

Related Articles

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

Sort by
Same author

PFAS free chemically amplified resists enabled by low activation energy hydrocarbon cage monomers.

Chemical science·2026
Same author

A Light-Activated Nickel Catalyst for the Carbonylation of Alkyl Halides.

Organic letters·2026
Same author

Inter-and Intramolecular (4+3) Cycloadditions With Epoxy Allylsilanes as Dienophiles.

Chemistry, an Asian journal·2026
Same author

Merging Photoredox and Palladium Photochemistry: Evidence for a Dual-Photon Approach to Aldehyde Synthesis.

Journal of the American Chemical Society·2026
Same author

A Chemical-Genetic Interaction Matrix Reveals Drug Mechanism and Genetic Architecture.

bioRxiv : the preprint server for biology·2026
Same author

Mechanism of the Stoltz-Grubbs (KO<sup>t</sup>Bu/Et<sub>3</sub>SiH) Silylation: Single-Electron Transfer is the Missing Link between the Heterolytic and Radical Pathways.

Angewandte Chemie (International ed. in English)·2025

Related Experiment Video

Updated: Jun 12, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
08:46

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)

Published on: November 22, 2016

Phospha-Münchnones: electronic structures and 1,3-dipolar cycloadditions.

Daniel J St-Cyr1, Marie S T Morin, Francine Bélanger-Gariépy

  • 1Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 2K6, Canada.

The Journal of Organic Chemistry
|May 21, 2010
PubMed
Summary

Researchers developed novel phospha-Munchnones, a new class of 1,3-dipoles, for efficient pyrrole synthesis. Their reactivity in cycloaddition reactions is tunable by varying the phosphorus (PR(3)) component, enabling selective pyrrole formation.

More Related Videos

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of &#945;-Imino &#947;-Lactones and Alkylidene Pyrazolones
10:17

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Published on: February 7, 2019

Related Experiment Videos

Last Updated: Jun 12, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
08:46

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)

Published on: November 22, 2016

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of &#945;-Imino &#947;-Lactones and Alkylidene Pyrazolones
10:17

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones

Published on: February 7, 2019

Area of Science:

  • Organic Chemistry
  • Heterocyclic Chemistry
  • Organophosphorus Chemistry

Background:

  • 1,3-dipoles are versatile synthons in organic chemistry.
  • Pyrroles are important heterocyclic compounds with broad applications.
  • Development of novel synthetic routes to pyrroles is an ongoing area of research.

Purpose of the Study:

  • To introduce a new class of 1,3-dipoles, termed phospha-Munchnones.
  • To investigate the cycloaddition reactions of phospha-Munchnones with alkynes for pyrrole synthesis.
  • To explore the influence of the phosphorus (PR(3)) substituent on reactivity and selectivity.

Main Methods:

  • Synthesis of phospha-Munchnones from imines, acid chlorides, PR(3), and base.
  • Cycloaddition reactions with various alkynes.
  • Spectroscopic analysis (1H, 13C, 31P NMR) and X-ray crystallography.
  • Computational studies using Density Functional Theory (DFT).

Main Results:

  • Phospha-Munchnones were successfully generated and characterized.
  • Cycloaddition reactions with alkynes yielded pyrroles with loss of phosphine oxides.
  • Reactivity and pyrrole yields were dependent on the PR(3) group; PhP(catechyl) showed optimal results.
  • Electron-poor phosphonites/phosphites favored cyclic 1,3-dipolar structures, while electron-rich phosphines favored acyclic ylides.
  • DFT calculations elucidated reaction mechanisms and transition state geometries.
  • Regioselective cycloadditions were observed with substituted alkynes due to electronic bias.

Conclusions:

  • Phospha-Munchnones represent a novel and useful class of 1,3-dipoles for pyrrole synthesis.
  • The choice of PR(3) group is critical for controlling reactivity and efficiency.
  • Understanding the electronic and structural properties of the dipoles guides the design of efficient cycloaddition reactions.
  • This methodology offers a new pathway for regioselective synthesis of substituted pyrroles.