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Arilaciones Heck enantioselectivas de alcoholes alqueniles acíclicos utilizando una estrategia de relevo redox

Erik W Werner¹, Tian-Sheng Mei, Alexander J Burckle

¹Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112, USA.

Science (New York, N.Y.)

|December 15, 2012

Resumen

Este estudio introduce una reacción de acoplamiento de Heck enantioselectiva para crear compuestos de aril carbonilo. El nuevo sistema catalizador logra una alta regioselectividad y enantioselectividad, ofreciendo una nueva ruta sintética para moléculas complejas.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

Los acoplamientos Heck asimétricos son cruciales para la síntesis de moléculas orgánicas complejas.
La comprensión limitada de la selectividad en la inserción migratoria y la eliminación del beta-hidruro dificulta el progreso.

Objetivo del estudio:

Desarrollar una variante de acoplamiento Heck enantioselectiva para la síntesis de productos de aril carbonilo.
Aclarar los factores que rigen la regioselectividad y la enantioselectividad en la reacción.

Principales métodos:

Utilizó un nuevo sistema de catalizador para el acoplamiento asimétrico de Heck.
Se emplean sales de arildiazonium como fuente de areno.
Reacciones investigadas con sustratos acíclicos de alquenol.

Principales resultados:

Se ha logrado la síntesis enantioselectiva de los productos beta, gamma o delta-arilo carbonilo.
Se ha demostrado una alta regioselectividad en la inserción migratoria y la migración de insaturación de alquenos.
Productos enantioméricos observados de configuraciones alquenicas opuestas, independientemente de la quiralidad del sustrato.

Conclusiones:

El sistema de catalizador desarrollado permite una síntesis enantioselectiva eficiente de compuestos de aril carbonilo.
Se obtuvieron conocimientos mecanicistas sobre la regioselectividad y la enantioselectividad.
Proporciona un método versátil utilizando ligandos y sales de aryldiazonium fácilmente accesibles.

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