Video Experimental Relacionado
Updated: Feb 16, 2026
10:10
Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
Published on: July 28, 2018
6.9K
Desfluoroalquilación catalítica de trifluorometilaromáticos con alquenos no activados
1Department of Chemistry and Winship Cancer Institute, Emory University , Atlanta, Georgia 30322, United States.
Journal of the American Chemical Society
|December 20, 2017
Resumen
Este estudio introduce un nuevo método catalítico para la funcionalización de compuestos trifluorometilaromáticos mediante la escisión de fuertes enlaces carbono-fluoro. El proceso crea valiosas moléculas fluoradas a partir de materiales de partida simples.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Química del fluor
Sus antecedentes:
- Los enlaces carbono-fluoro (C-F) en sistemas trifluorometilaromáticos (Ar-CF3) son excepcionalmente fuertes y difíciles de funcionalizar.
- La modificación selectiva de estos enlaces es crucial para la síntesis de nuevos compuestos orgánicos fluorados.
Objetivo del estudio:
- Desarrollar un nuevo enfoque catalítico para la funcionalización selectiva de los sistemas Ar-CF3.
- Permitir la formación de subestructuras fluoradas médicamente relevantes con un alto control regional.
Principales métodos:
- Utilizando un catalizador fotorredóxico para la reducción de un solo electrón de sustratos Ar-CF3.
- Inicia la escisión del enlace C-F para formar radicales difluorobenzílicos.
- Utilizando el acoplamiento intermolecular con alquenos en un proceso de defluoroalquilación.
- Implementando un catalizador de reversión de polaridad para la terminación radical.
Principales resultados:
- Funcionalización selectiva exitosa de enlaces fuertes C-F en sistemas Ar-CF3.
- Formación de radicales difluorobenzílicos a través de la escisión C-F.
- Acoplamiento eficiente de radicales con alceno, lo que lleva a la defluoroalquilación.
- Demostración de un protocolo catalítico suave aplicable a diversos sustratos.
- Generación de subestructuras fluoradas médicamente relevantes con un control regional completo.
Conclusiones:
- El protocolo catalítico desarrollado ofrece un método suave y eficiente para la funcionalización de Ar-CF3.
- Este enfoque proporciona acceso a valiosos compuestos fluorados con un control estructural preciso.
- La estrategia tiene un potencial significativo para el descubrimiento de fármacos y la ciencia de los materiales.
Videos de Conceptos Relacionados
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
9.1K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
9.1K
01:17Electrophilic Aromatic Substitution: Friedel–Crafts Alkylation of Benzene
8.4K
Friedel–Crafts reactions were developed in 1877 by the French chemist Charles Friedel and the American chemist James Crafts. Friedel–Crafts alkylation refers to the replacement of an aromatic proton with an alkyl group via electrophilic aromatic substitution. A Lewis acid catalyst such as aluminum chloride reacts with an alkyl halide to form a carbocation. The resulting carbocation then reacts with the aromatic ring and undergoes a series of electron rearrangements before giving the final...
8.4K
03:08Hydroboration-Oxidation of Alkenes
11.6K
In addition to the oxymercuration–demercuration method, which converts the alkenes to alcohols with Markovnikov orientation, a complementary hydroboration-oxidation method yields the anti-Markovnikov product. The hydroboration reaction, discovered in 1959 by H.C. Brown, involves the addition of a B–H bond of borane to an alkene giving an organoborane intermediate. The oxidation of this intermediate with basic hydrogen peroxide forms an alcohol.
11.6K
02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
21.4K
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.
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.
21.4K
01:26Limitations of Friedel–Crafts Reactions
7.0K
Several restrictions limit the use of Friedel–Crafts reactions. First, the halogen in the alkyl halide must be attached to an sp3-hybridized carbon for the Friedel–Crafts reactions to occur. Vinyl or aryl halides do not react since the carbocations formed are unstable under the reaction conditions. Second, Friedel–Crafts alkylation is susceptible to carbocation rearrangement, and the major products obtained have a rearranged carbon skeleton. In contrast, the acylium ion is...
7.0K
00:51Base-Promoted α-Halogenation of Aldehydes and Ketones
4.2K
α-Halogenation of aldehydes and ketones is a reaction involving the substitution of α hydrogens with halogens in the presence of a base. The reaction begins with the abstraction of α hydrogen by the base to produce a nucleophilic enolate ion. This intermediate undergoes a subsequent nucleophilic substitution with the halogen to produce a monohalogenated carbonyl compound. If the starting substrate has more than one α hydrogen, it is difficult to stop the reaction...
4.2K