Video Experimental Relacionado

Updated: Sep 20, 2025

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Published on: April 4, 2014

Síntesis de Dialquilcarbinol Enantioselectivo Ni-Catalizado a través del Acoplamiento Cruzado Decarboxilativo:

Yang Gao¹, Benxiang Zhang¹, Laura Levy¹

¹Department of Chemistry, Scripps Research, 10550 North Torrey Pines Road, La Jolla, California 92037, United States.

Journal of the American Chemical Society

|June 7, 2022

Resumen

Los investigadores desarrollaron las primeras alquilaciones decarboxilativas enantioselectivas de tipo Negishi utilizando ésteres redox-activos (RAE). Este método basado en radicales simplifica la síntesis de los dialquilocarbinolos enantiopuros.

Área de la Ciencia:

Química orgánica
Metodología sintética
Catálisis

Sus antecedentes:

La síntesis enantioselectiva es crucial para los productos farmacéuticos y los materiales.
Los acoplamientos descarboxilativos ofrecen rutas atómicas económicas para moléculas complejas.
Los acoplamientos de tipo Negishi tradicionalmente incluyen reactivos organozinc.

Objetivo del estudio:

Informar sobre la primera alquilación decarboxilada enantioselectiva del tipo Negishi de los ácidos alfa-oxicarboxílicos.
Establecer una estrategia de retrosíntesis basada en radicales para los dialquilocarbinolos enantiopuros.
Desarrollar condiciones generales y demostrar una amplia aplicabilidad.

Principales métodos:

Utilizando ésteres redox-activos (RAE) como productos intermedios clave.
Empleando la química basada en el radical para la formación de enlaces C-C.
Optimización de las condiciones de reacción para la enantioselectividad y el rendimiento.

Principales resultados:

Desarrollo exitoso de la primera alquilación decarboxilativa enantioselectiva de tipo Negishi para ácidos alfa-oxicarboxílicos.
Demostración de una nueva retrosíntesis basada en radicales para los carbinolos quirales.
Aplicaciones extensas que muestran la utilidad sintética y la simplificación del método.

Conclusiones:

La transformación mediada por RAE desarrollada proporciona una nueva herramienta poderosa para la síntesis asimétrica.
Este método ofrece un enfoque simplificado para los dialquilocarbinolos enantiopuros.
El estudio pone de relieve el potencial de la química radical en el acceso a bloques de construcción quirales valiosos.

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

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Published on: November 27, 2015

Videos de Conceptos Relacionados

Alkylation of β-Diester Enolates: Malonic Ester Synthesis

Alkylation of β-Diester Enolates: Malonic Ester Synthesis

Malonic ester synthesis is a method to obtain α substituted carboxylic acids from ꞵ-diesters such as diethyl malonate and alkyl halides.

β-Dicarbonyl Compounds via Crossed Claisen Condensations

β-Dicarbonyl Compounds via Crossed Claisen Condensations

Crossed Claisen condensations are base-promoted reactions between two different ester molecules producing β-dicarbonyl compounds. The reaction involving esters, with both containing α hydrogen, results in a mixture of four different products that are difficult to isolate. This reduces the synthetic utility of the reaction.

Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

Robinson annulation is a base-catalyzed reaction for the synthesis of 2-cyclohexenone derivatives from 1,3-dicarbonyl donors (such as cyclic diketones, β-ketoesters, or β-diketones) and α,β-unsaturated carbonyl acceptors. Named after Sir Robert Robinson, who discovered it, this reaction yields a six-membered ring with three new C–C bonds (two σ bonds and one π bond).

Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview

Vicinal Diols via Reductive Coupling of Aldehydes or Ketones: Pinacol Coupling Overview

Wilhelm Rudolph Fittig discovered the pinacol coupling reaction in 1859. It is a radical dimerization reaction and involves the reductive coupling of aldehydes or ketones in the presence of hydrocarbon solvent to yield vicinal diols.

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.

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

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...