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Acoplamiento cruzado reductor asimétrico catalizado por níquel para acceder a los 1,1-diarilalcanos

Kelsey E Poremba¹, Nathaniel T Kadunce¹, Naoyuki Suzuki¹

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

|April 14, 2017

Resumen

Una nueva reacción catalizada por níquel crea enantioenriquecidos 1,1-diarilalcanos a partir de precursores simples. Este método utiliza un nuevo ligando quiral de bioxazolina para un alto rendimiento y selectividad, acomodando diversos compuestos heterocíclicos.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Los 1,1-diarilalcanos son motivos estructurales importantes en productos farmacéuticos y materiales.
El desarrollo de métodos eficientes y enantioselectivos para su síntesis sigue siendo un reto.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico asimétrico para la síntesis de enantioenriquecidos de 1,1-diarilalcanos.
Introducir un nuevo ligando quiral de bioxazolina para mejorar el rendimiento catalítico.

Principales métodos:

Reacción asimétrica de acoplamiento cruzado reductivo catalizada por níquel.
Los ioduros de (hetero) arilo y los cloruros bencílicos utilizados como socios de acoplamiento.
Se utilizó un ligando quiral de bioxazolina (4-heptyl-BiOX, L1) recientemente desarrollado.

Principales resultados:

Se han sintetizado con éxito enantioenriquecidos de 1,1-diarilalcanos con alto rendimiento y enantioselectividad.
El ligando quiral desarrollado (L1) fue crucial para lograr resultados óptimos.
La reacción demostró un amplio alcance de sustrato, tolerando varios socios de acoplamiento heterocíclico como piridinas, pirimidinas, indolos y piperidinas.

Conclusiones:

Se ha establecido un método eficaz de acoplamiento reductivo asimétrico catalizado por Ni para la síntesis de 1,1-diarilalcanos.
El nuevo ligando quiral de la bioxazolina permite una alta enantioselectividad y rendimiento.
Esta metodología ofrece una ruta versátil a compuestos quirales valiosos con diversas funcionalidades heterocíclicas.

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