Search research articles

ACERCA DE JoVE

Visión General Liderazgo Blog Centro de Ayuda JoVE

AUTORES

Proceso de Publicación Consejo Editorial Alcance y Políticas Revisión por Pares Preguntas Frecuentes Enviar

BIBLIOTECARIOS

Testimonios Suscripciones Acceso Recursos Consejo Asesor de Bibliotecas Preguntas Frecuentes

INVESTIGACIÓN

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archivo

EDUCACIÓN

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Centro de Recursos para Profesores Sitio de Profesores

Términos y Condiciones de Uso

Política de Privacidad

Videos de Conceptos Relacionados

Elimination Reactions

Elimination Reactions

A nucleophile can react with an alkyl halide to give the substitution product by displacing the halogen. Or it can function as a base to give the elimination product by deprotonation of the neighboring carbon to form an alkene. In an elimination reaction, the substrate loses two groups from adjacent carbons forming at least one π bond. The carbon attached to the halogen is called the α carbon, while the adjacent carbon is called the β carbon; hence, these reactions are called β elimination or...

Preparation of Alkynes: Dehydrohalogenation

Preparation of Alkynes: Dehydrohalogenation

Introduction
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.

Acid Halides to Alcohols: LiAlH4 Reduction

Acid Halides to Alcohols: LiAlH₄ Reduction

Acid halides are reduced to alcohols in the presence of a strong reducing agent like lithium aluminum hydride.
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...

Amides to Amines: LiAlH4 Reduction

Amides to Amines: LiAlH₄ Reduction

Amide reduction with strong reducing agents like lithium aluminum hydride proceeds through a nucleophilic acyl substitution to form amines. Primary, secondary, and tertiary amides yield primary, secondary, and tertiary amines, respectively.
Amide reduction requires two equivalents of the reducing agent, acting as a source of hydride ions. As shown in the figure, the reaction is initiated with a nucleophilic attack by the hydride ion at the carbonyl carbon to form a tetrahedral intermediate.

Nitriles to Amines: LiAlH4 Reduction

Nitriles to Amines: LiAlH₄ Reduction

Nitriles are reduced to amines in the presence of strong reducing agents like lithium aluminum hydride through a typical nucleophilic acyl substitution. The reaction requires two equivalents of the reducing agent. The reducing agent acts as a source of hydride ions.
As shown below, the mechanism involves three steps. Firstly, the hydride ion acting as a nucleophile attacks the nitrile carbon to form an anion. In the second step, a second equivalent of the hydride ion attacks the anion to...

Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride

Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride

Radical substitution reactions can be used to remove functional groups from molecules. The hydrogenolysis of alkyl halides is one such reaction, where the weak Sn–H bond in tributyltin hydride reacts with alkyl halides to form alkanes. Here, the reagent Bu3SnH yields tributyltin halide as a byproduct.
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...

También podría leer

Artículos Relacionados

Artículos vinculados a este trabajo por autores compartidos, revista y gráfico de citas.

Ordenar por

Same author

Assembly and Reactions of Artificial Metalloenzymes in <i>Streptomyces albus</i>.

Journal of the American Chemical Society·2026

Same author

Uranyl Tris(benzoate) Photocatalysts for Site-Selective Hydrocarbon Functionalization.

Journal of the American Chemical Society·2026

Same author

Origins of the selectivity of late transition metals of Group 9 and Group 10 for oxidative addition of C-H <i>vs.</i> C-Cl bonds.

Chemical science·2026

Same author

Direct Observation of Selective Migratory Insertion of Unactivated Terminal Alkenes into Ir-N Bonds.

Journal of the American Chemical Society·2026

Same author

Mechanism-Inspired Ligand Design for Efficient Copper-Catalyzed C-N Coupling of Aryl and Heteroaryl Chlorides.

Journal of the American Chemical Society·2026

Same author

Microstructure of amide-functionalized polyethylenes determined by NMR relaxometry.

Chemical science·2026

Search research articles

Video Experimental Relacionado

Updated: Jul 18, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Published on: January 3, 2018

Eliminaciones de beta-arilo de los complejos Rh (I) iminyl.

Pinjing Zhao¹, John F Hartwig

¹Department of Chemistry, Yale University, PO Box 208107 New Haven, Connecticut 06520-8107, USA.

Journal of the American Chemical Society

|August 18, 2005

Resumen

Este estudio detalla las reacciones de eliminación de beta-Aryl en complejos de iminyl de rodio, formando complejos de arilo de rodio y nitriles. La investigación aclara el mecanismo y las aptitudes migratorias de los grupos arilo en estas transformaciones.

Más Videos Relacionados

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction

Published on: August 23, 2018

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

Videos de Experimentos Relacionados

Last Updated: Jul 18, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Published on: January 3, 2018

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction

Heterogeneous Removal of Water-Soluble Ruthenium Olefin Metathesis Catalyst from Aqueous Media Via Host-Guest Interaction

Published on: August 23, 2018

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex

Published on: July 27, 2022

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Catalización con el rodio.
Mecanismos de reacción Mecanismos de reacción

Sus antecedentes:

Los complejos de iminyl son versátiles intermediarios en la química organometálica.
Comprender la eliminación de beta-Aryl es crucial para el diseño de ciclos catalíticos.

Objetivo del estudio:

Informar sobre la síntesis y caracterización de complejos de iminyl de rodio.
Para investigar la vía de reacción de eliminación de beta-Aryl y la cinética.
Para determinar las aptitudes migratorias de varios grupos arilos.

Principales métodos:

Síntesis de complejos de iminyl a través de la reacción de [Rh(COE) Cl]2, fosfina e iminas.
Difracción de rayos X para la caracterización estructural de un complejo.
Estudios de descomposición térmica en diferentes disolventes (ciclohexano, benceno).
Estudios cinéticos para determinar los órdenes de reacción con respecto a la fosfina y el nitrilo.

Principales resultados:

Se sintetizaron con éxito los complejos de iminyl de rodio [Rh(PEt3) 3 ((N=CArAr') ].
La eliminación de Beta-Aryl procedió en altos rendimientos para formar complejos de rodio arilo y nitriles libres.
Se encontró que las aptitudes migratorias de Aryl eran: o-anisil > fenil > p-anisil y o-tolyl.
Los estudios cinéticos indicaron una dependencia inversa de primer orden en la fosfina y de orden cero en el nitrilo.

Conclusiones:

La eliminación de Beta-Aryl probablemente procede a través de la disociación de la fosfina para formar un intermediario de 14 electrones.
La aptitud migratoria de los grupos arilo está influenciada por factores electrónicos y estéricos.
Este trabajo proporciona información sobre el mecanismo de escisión de enlaces C-C en complejos de rodio.