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Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

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Ni-Electrocatalítico Enantioselectivo Doblemente Descarboxilativo C(sp³) -C(sp³) Acoplamiento cruzado

Yang Gao¹, Benxiang Zhang¹, Jiayan He¹

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

Journal of the American Chemical Society

|May 16, 2023

Resumen

Este estudio introduce la primera reacción de acoplamiento cruzado enantioselectiva doblemente descarboxilada. Este nuevo método sintetiza eficientemente amidas quirales con estereocentros α-alquilados utilizando electrocatálisis de níquel.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Las reacciones de acoplamiento descarboxilativo son herramientas valiosas en la síntesis orgánica.
El desarrollo de variantes enantioselectivas sigue siendo un desafío importante.
La electrocatálisis de níquel ofrece un enfoque sostenible para las transformaciones desafiantes.

Objetivo del estudio:

Para revelar los primeros ejemplos de doble descarboxilación enantioselectiva.
Desarrollar un nuevo método para sintetizar amidas quirales con estereocentros α-alquilados.
Para explorar la utilidad de esta reacción en la síntesis de moléculas complejas.

Principales métodos:

Utilizando las semiamidas de malonato y los ácidos carboxílicos primarios.
Formación de ésteres redox activos.
Utilizando condiciones electrocatalíticas de níquel con un nuevo ligando quiral basado en PyBox.

Principales resultados:

Se logra un acoplamiento suave de diversos sustratos.
Se ha demostrado una amplia tolerancia del grupo funcional.
Se obtiene constantemente una elevada enantioselectividad (ee).

Conclusiones:

Estableció un nuevo paradigma para el acoplamiento cruzado reductor radical-radical enantioselectivo.
Mostró el potencial de la reacción para agilizar las rutas sintéticas.
Destacó la versatilidad y la eficacia de la metodología desarrollada.

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