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Acoplamiento catalítico enantioconvergente de electrofilos secundarios y terciarios con olefinas
Zhaobin Wang1, Haolin Yin1, Gregory C Fu2
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA.
Nature
|October 20, 2018
Resumen
Este estudio introduce un nuevo método para crear enlaces carbono-carbono con una estereoquímica precisa. Un catalizador quiral de níquel permite el acoplamiento enantioselectivo de haluros de alquilo con olefinas, ofreciendo una nueva ruta para la síntesis de moléculas complejas.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Estereoquímica
Sus antecedentes:
- Los enlaces alquil-alquil forman la columna vertebral de las moléculas orgánicas.
- El control de la estereoquímica en la formación de enlaces alquilo-alquilo es crucial pero desafiante.
- Los métodos existentes para el acoplamiento enantioconvergente tienen limitaciones.
Objetivo del estudio:
- Desarrollar una nueva estrategia para la formación de enlaces alquilo-alquilo enantioselectivos.
- Para permitir el acoplamiento de electrofilos alquilo racémicos con olefinas.
- Para controlar la estereoquímica durante la construcción de enlaces carbono-carbono.
Principales métodos:
- Utilizó un catalizador quiral de níquel para las reacciones de acoplamiento cruzado.
- Los haluros de alquilo racémicos empleados (secundarios y terciarios) como electrófilos.
- Halidos de alquilo acoplados con olefinas en presencia de un hidrosilano.
Principales resultados:
- Se ha logrado la formación de enlaces alquilo-alquilo enantioselectivos.
- Se ha demostrado el éxito del acoplamiento cruzado de varios haluros de alquilo racémicos con olefinas.
- Se obtiene una buena enantioselectividad y rendimiento en condiciones de reacción suaves.
Conclusiones:
- Desarrolló un método nuevo y eficiente para el acoplamiento alquilo-alquilo enantioselectivo.
- El enfoque es aplicable a sustratos difíciles como los haluros de alquilo secundarios y terciarios.
- Esto abre caminos para estrategias de formación de enlaces alquilo-alquilo enantioconvergentes más generales.
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