Related Experiment Video

Updated: Aug 15, 2025

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
08:25

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs

Published on: January 17, 2020

7.3K

H-Bonded Counterion-Directed Catalysis: Enantioselective Gold(I)-Catalyzed Addition to 2-Alkynyl Enones as a Case

Àlex Martí1,2, Marc Montesinos-Magraner1, Antonio M Echavarren1,2

  • 1Institute of Chemical Research of Catalonia (ICIQ) Barcelona Institute of Science and Technology (BIST) Av. Països Catalans 16 43007 Tarragona Spain.

European Journal of Organic Chemistry
|January 2, 2023
PubMed

Keywords:
Asymmetric catalysisChiral counterionGoldHydrogen bondingYnenones

More Related Videos

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate06:46

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Published on: June 21, 2017

7.5K
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species08:12

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

Published on: August 16, 2018

10.1K

Related Concept Videos

Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction01:26

Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction

α-Substituted ketones or aldehydes can be synthesized from enamines by the Stork enamine reaction, named after its pioneer Gilbert Stork. Enamines are useful synthetic intermediates where the lone pair on nitrogen is in conjugation with the C=C bond. They resemble enolate ions, as the resonance forms of both species have a nucleophilic α carbon.
3.5K
α-Alkylation of Ketones via Enolate Ions01:10

α-Alkylation of Ketones via Enolate Ions

Ketones with α protons are deprotonated by strong bases like lithium diisopropylamide (LDA) to form enolate ions. The anion is stabilized by resonance, and its hybrid structure exhibits negative charges on the carbonyl oxygen and the α carbon. This ambident nucleophile can attack an electrophile via two possible sites: the carbonyl oxygen, known as O-attack, or the α carbon, known as C-attack. The nucleophilic attack via the carbanionic site is preferred. This is due to the...
3.3K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation02:17

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.4K
Regioselectivity of Electrophilic Additions-Peroxide Effect02:35

Regioselectivity of Electrophilic Additions-Peroxide Effect

In the presence of organic peroxides, the addition of hydrogen bromide to an alkene yields the isomer that is not predicted by Markovnikov’s rule. For example, the addition of hydrogen bromide to 2-methylpropene in the presence of peroxides gives 1-bromo-2-methylpropane. This addition reaction proceeds via a free radical mechanism, which reverses the regioselectivity. The free radical reaction mechanism involves three stages: initiation, propagation, and termination.
8.8K
Electrophilic Addition to Alkynes: Hydrohalogenation02:35

Electrophilic Addition to Alkynes: Hydrohalogenation

Electrophilic addition of hydrogen halides, HX (X = Cl, Br or I) to alkenes forms alkyl halides as per Markovnikov's rule, where the hydrogen gets added to the less substituted carbon of the double bond. Hydrohalogenation of alkynes takes place in a similar manner, with the first addition of HX forming a vinyl halide and the second giving a geminal dihalide.
10.1K
Conjugate Addition of Enolates: Michael Addition01:08

Conjugate Addition of Enolates: Michael Addition

The attack of a nucleophile at the β carbon of an α,β-unsaturated carbonyl compound is called conjugate addition. Conjugate addition reactions of active methylene compounds, such as β-diketones, β-keto esters, β-keto nitriles, and α-nitro ketones, are called Michael addition reactions.
2.8K