Video Experimental Relacionado

Updated: Jun 20, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides

Published on: May 26, 2019

Terminación reductora y brominativa de la ciclización del alquenol en reacciones aeróbicas catalizadas por cobalto

Dominik Schuch¹, Patrick Fries, Maike Dönges

¹Fachbereich Chemie, Organische Chemie, Technische Universität Kaiserslautern, D-67663 Kaiserslautern, Germany.

Journal of the American Chemical Society

|August 22, 2009

Resumen

Este estudio demuestra la generación estereoselectiva de radicales tetrahidrofur-2-ilmetil a través de la oxidación catalizada por cobalto aeróbico de pent-4-en-1-ols. Estos radicales fueron atrapados para producir tetrahidrofuranos funcionalizados con alta utilidad sintética.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis es la catálisis.
Química Radical La Química Radical es una ciencia

Sus antecedentes:

Los derivados de tetrahidrofurano prevalecen en productos naturales y productos farmacéuticos.
La síntesis eficiente de tetrahidrofuranos funcionalizados sigue siendo un desafío clave en la química orgánica.

Objetivo del estudio:

Desarrollar un método estereoselectivo para la generación de radicales tetrahidrofur-2-ilmetil.
Para utilizar estos radicales en la síntesis de diversos tetrahidrofuranos funcionalizados.

Principales métodos:

La oxidación catalizada por el cobalto aeróbico (II) de pent-4-en-1-ol sustituido.
Generación estereoselectiva de radicales tetrahidrofur-2-ilmetilo.
Captura de radicales con varios dienófilos y electrófilos (por ejemplo, ciclohexa-1,4-dieno, acrilonitrilo).

Principales resultados:

Se logró una exitosa generación estereoselectiva de radicales tetrahidrofur-2-ilmetil.
Se sintetizó una gama de tetrahidrofuranos funcionalizados en rendimientos sintéticamente útiles.
El método demostró ser eficaz con varios agentes de captura, mostrando su versatilidad.

Conclusiones:

La oxidación aeróbica catalizada por cobalto (II) desarrollada proporciona una nueva ruta a los tetrahidrofuranos funcionalizados.
Esta metodología ofrece un enfoque estereoselectivo y eficiente para la síntesis de valiosos compuestos heterocíclicos.

Más Videos Relacionados

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy

Versatile CO₂ Transformations into Complex Products: A One-pot Two-step Strategy

Published on: November 9, 2019

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions

Published on: November 30, 2022

Videos de Conceptos Relacionados

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation

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.

Hydroboration-Oxidation of Alkenes

Hydroboration-Oxidation of Alkenes

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.

Radical Anti-Markovnikov Addition to Alkenes: Mechanism

Radical Anti-Markovnikov Addition to Alkenes: Mechanism

The reaction of hydrogen bromide with alkenes in the presence of hydroperoxides or peroxides proceeds via anti-Markovnikov addition. The radical chain reaction comprises initiation, propagation, and termination steps.
The mechanism starts with chain initiation, which involves two steps. In the first chain initiation step, a weak peroxide bond is homolytically cleaved upon mild heating to form two alkoxy radicals. In the second initiation step, a hydrogen atom is abstracted by the alkoxy radical...

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction

The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.

Radical Anti-Markovnikov Addition to Alkenes: Overview

Radical Anti-Markovnikov Addition to Alkenes: Overview

The addition of hydrogen bromide to alkenes in the presence of hydroperoxides or peroxides proceeds via an anti-Markovnikov pathway and yields alkyl bromides.

Halogenation of Alkenes

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.