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Síntesis de silanos alilicos enriquecidos con enantio mediante acoplamiento cruzado reductor catalizado por níquel

Julie L Hofstra¹, Alan H Cherney¹, Ciara M Ordner¹

¹The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.

Journal of the American Chemical Society

|December 5, 2017

Resumen

Una nueva reacción catalizada por níquel crea silanos alelicos quirales con alta precisión. Estos compuestos versátiles permiten la síntesis estereospecífica de moléculas complejas, lo que demuestra una excelente transferencia de quiralidad.

Área de la Ciencia:

Química organometálica
Catálisis asimétrica
Química orgánica sintética

Sus antecedentes:

Los silanos alilicos son valiosos intermediarios sintéticos.
El desarrollo de métodos enantioselectivos para su síntesis sigue siendo un desafío.
La catálisis del níquel ofrece una vía prometedora para nuevas transformaciones.

Objetivo del estudio:

Desarrollar una reacción asimétrica de acoplamiento cruzado reductor catalizado por níquel.
Para sintetizar enantio enriquecido silanos alilicos de manera eficiente.
Para explorar la utilidad sintética de las silanas alilicas quirales.

Principales métodos:

Catálisis asimétrica de níquel para el acoplamiento cruzado reductivo.
Condiciones de reacción leves.
Demostración de la tolerancia del grupo funcional.

Principales resultados:

Preparación exitosa de silanos alilicos enriquecidos con enantio.
Se obtiene una alta enantioselectividad en la alquenilación reductiva.
Los silanos alílicos quirales sufren transformaciones estereospecíficas, incluidas las reacciones intramoleculares de Hosomi-Sakurai.

Conclusiones:

El método desarrollado proporciona acceso a valiosos silanos alelicos quirales.
La metodología muestra una amplia tolerancia del grupo funcional y condiciones leves.
Se observa una excelente transferencia de quiralidad en las reacciones estereospecíficas posteriores.

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