Video Experimental Relacionado

Updated: Apr 1, 2026

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

Reacciones de intercambio de doble FLP-alquina: una ruta fácil hacia los heterociclos Te/B

Fu An Tsao¹, Levy Cao¹, Stefan Grimme²

¹Department of Chemistry, University of Toronto , 80 St. George St., Toronto, Ontario Canada M5S 3H6.

Journal of the American Chemical Society

|October 9, 2015

Resumen

Se sintetizaron nuevos heterociclos de telurio y boro mediante reacciones secuenciales de intercambio de alquinos. Estas reacciones son regioselectivas, toleran grupos funcionales y ofrecen potencial para una mayor derivación.

Área de la Ciencia:

Química organometálica
Química Heterocíclica
Química del boro
Química del telurio

Sus antecedentes:

Los heterociclos de telurio y boro son una clase emergente de compuestos con propiedades químicas únicas.
El desarrollo de rutas sintéticas eficientes para nuevas estructuras heterocíclicas es crucial para avanzar en la síntesis química.

Objetivo del estudio:

Desarrollar una nueva metodología sintética para acceder a nuevos heterociclos de telurio y boro.
Investigar el alcance y las limitaciones de las reacciones de intercambio de alquinos que involucran sistemas de telurio y boro.

Principales métodos:

Se emplearon reacciones secuenciales [4 + 2] de cicloadición y eliminación de alquinos.
Las reacciones incorporaron dos equivalentes de alquinas terminales, lo que condujo a la formación de nuevas estructuras heterocíclicas.
Se utilizaron cálculos de la Teoría Funcional de Densidad (DFT) para dilucidar el mecanismo de reacción.

Principales resultados:

Se sintetizaron con éxito once nuevos heterociclos de telurio y boro.
Las reacciones de intercambio de alquinas demostraron una alta regioselectividad.
Las reacciones fueron tolerantes a varios grupos funcionales, lo que indica una amplia aplicabilidad.
Los estudios de DFT confirmaron un mecanismo de par de Lewis frustrado que involucra las interacciones de telurio y boro con las alquinas.

Conclusiones:

Se ha establecido un método nuevo y eficiente para sintetizar los heterociclos de telurio y boro.
La regioselectividad demostrada y la tolerancia del grupo funcional ponen de relieve la utilidad sintética de este enfoque.
Las ideas mecanicistas proporcionan una base para una mayor exploración de las reacciones relacionadas.

Más Videos Relacionados

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Published on: July 28, 2018

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

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

Published on: August 16, 2018

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.

Cycloaddition Reactions: MO Requirements for Thermal Activation

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.

Preparation of Alkynes: Alkylation Reaction

Preparation of Alkynes: Alkylation Reaction

Introduction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.

Cycloaddition Reactions: Overview

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.

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

[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.

Electrophilic Aromatic Substitution: Friedel–Crafts Alkylation of Benzene

Electrophilic Aromatic Substitution: Friedel–Crafts Alkylation of Benzene

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...