Related Experiment Video
Updated: Jun 3, 2026
07:50
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Conjugate additions to alkylidene bis(sulfoxides)
Franck Brebion1, Guillaume Vincent, Saloua Chelli
1UPMC University Paris 06, Institut Parisien de Chimie Moléculaire (UMR CNRS 7201), 4 place Jussieu, C. 229, 75005 Paris, France.
Chemistry, an Asian Journal
|March 15, 2011
Summary
This study explores adding nucleophiles to bis(sulfoxides), finding alkoxides yield selective reactions. Organometallics offer a route to inverted stereoselectivity in these conjugate additions.
Area of Science:
- Organic Chemistry
- Stereoselective Synthesis
Background:
- Alkylidene bis(sulfoxides) are versatile substrates in organic synthesis.
- Understanding conjugate addition reactions is crucial for developing new synthetic methodologies.
Purpose of the Study:
- To investigate the conjugate addition of various anionic nucleophiles to alkylidene bis(sulfoxides).
- To explore the influence of reaction conditions on diastereoselectivity.
- To establish synthetic routes to novel sulfinyl-containing compounds.
Main Methods:
- Conjugate addition reactions utilizing alkoxides, azides, and organometallic reagents (copper).
- Variations in solvents and counteranions to study their effects.
- Stereochemical analysis to determine diastereoselectivity.
- Computational modeling to rationalize observed stereochemical outcomes.
Main Results:
- Alkoxide additions proceeded with high yields and significant diastereoselectivity, tunable by solvent and counteranion.
- Azide nucleophiles enabled the synthesis of sulfinyl-substituted triazoles.
- Organometallic reagents, particularly copper compounds, facilitated conjugate addition with complete inversion of stereoselectivity.
- Modelizations successfully explained the observed diastereoselectivity patterns.
Conclusions:
- Conjugate addition to alkylidene bis(sulfoxides) is a versatile method for creating complex molecules.
- The choice of nucleophile and reaction conditions allows for precise control over stereochemical outcomes.
- This work provides valuable insights into stereoselective synthesis and expands the utility of bis(sulfoxide) chemistry.
Related Concept Videos
01:09Conjugate Addition to α,β-Unsaturated Carbonyl Compounds
α,β-Unsaturated carbonyl compounds are molecules bearing a carbonyl and alkene functionality in conjugation with each other. The conjugation in the molecule leads to three resonance structures. The hybrid form exhibits two probable electrophilic sites: the carbonyl carbon and the β carbon.
01:27Conjugate Addition (1,4-Addition) vs Direct Addition (1,2-Addition)
α,β-Unsaturated carbonyl compounds with two electrophilic sites, the carbonyl carbon, and the β carbon, are susceptible to nucleophilic attack via two modes: conjugate or 1,4-addition and direct or 1,2-addition.
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are formed faster owing to...
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are formed faster owing to...
02:26Preparation and Reactions of Sulfides
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.
02:24Introduction to Electrophilic Addition Reactions of Alkenes
The double bond in a simple, unconjugated alkene is a region of high electron density that can act as a weak base or a nucleophile. The filled π orbital (HOMO) of the double bond can interact with the empty LUMO of an electrophile. A bonding interaction occurs when the electrophile attacks between the two carbons; the electrophile then accepts a pair of electrons from the π bond and undergoes addition across the double bond, yielding a single product.
Addition and elimination reactions can be...
Addition and elimination reactions can be...
02:38Electrophilic Addition to Alkynes: Halogenation
Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
01:14Electrophilic 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.