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Funcionalización asimétrica de tres componentes de 1,2-dicarbonio catalizado de alquenos no activados a través de la

Omar Apolinar¹, Taeho Kang¹, Turki M Alturaifi²

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

Journal of the American Chemical Society

|October 12, 2022

Resumen

Este estudio presenta una nueva reacción catalizada por níquel para crear moléculas complejas a partir de alquenos y yoduros de arilo simples. El método logra una alta estereoselectividad, ofreciendo una poderosa herramienta para la síntesis asimétrica.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

El desarrollo de métodos eficientes para la formación de enlaces carbono-carbono es crucial en la síntesis orgánica.
La catálisis asimétrica permite la síntesis selectiva de moléculas quirales, que son vitales en los productos farmacéuticos y la ciencia de los materiales.
La catálisis del níquel ofrece una alternativa rentable y versátil a los catalizadores de metales preciosos.

Objetivo del estudio:

Para revelar una 1,2-dicarbofuncionalización asimétrica de alquenos no activados utilizando yoduros de arilo y reactivos de organoboron.
Explorar el alcance y las limitaciones del sistema catalítico desarrollado.
Para aclarar el mecanismo de la reacción catalizada por níquel.

Principales métodos:

Utilizando un catalizador de níquel en combinación con un ligando quiral de bioxazolina.
Utilizando yoduros de arilo y ésteres arilo/alquenilborónicos como socios de acoplamiento.
Investigando la reacción con los alquenos terminales y 1,2-disubstituidos.
La combinación de estudios experimentales con análisis computacional (DFT) para comprender la vía de reacción.

Principales resultados:

Se ha logrado la 1,2-dicarbofuncionalización asimétrica de alquenos no activados con buenos rendimientos y alta enantioselectividad.
Tolerancia demostrada para una amplia gama de nucleófilos arilo y alquenilo.
Se aplicó con éxito la reacción a alquenos internos 1,2-disubstituidos, formando dos estereocentros contiguos con alta diastereoselectividad.
Se identificó una vía catalítica de caparazón cerrada que incluye un paso de inserción migratoria enantiodeterminante.

Conclusiones:

El sistema catalítico de níquel/bioxazolina desarrollado proporciona una vía eficaz para la dicarbofuncionalización asimétrica del 1,2.
La reacción establece múltiples estereocentros con alto control, aplicables a diversos sustratos.
Las interacciones sinérgicas entre el grupo dirigente y el ligando gobiernan el resultado estereocímico.

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