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sSPhos: un ligando general para la desaromatización de fenoles arilativos enantioselectivos mediante catálisis de

Max Kadarauch¹, David M Whalley¹, Robert J Phipps¹

¹Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom.

Journal of the American Chemical Society

|November 16, 2023

Resumen

Este estudio introduce un nuevo método de catálisis del paladio utilizando un ligando sulfonado quiral (sSPhos) para la dearomatización arilativa del fenol. Este enfoque crea de manera eficiente espirociclohexadienonas enriquecidas con enantio y otros andamios complejos, simplificando la síntesis.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

La desaromatización arilativa del fenol es crucial para la síntesis de andamios complejos de ciclohexanona.
La síntesis asimétrica requiere ligandos quirales específicos para cada nueva variación del andamio, lo que limita la eficiencia.
Los métodos anteriores para las espirociclohexadienonas enriquecidas con enantio a menudo producían productos racémicos.

Objetivo del estudio:

Desarrollar un ligando quiral versátil para la desaromatización arilativa del fenol.
Para permitir un acceso eficiente a las espirociclohexadienonas altamente enriquecidas y otros andamios utilizando un solo ligando.
Demostrar la utilidad de la catálisis dirigida electrostáticamente para simplificar la síntesis de moléculas complejas.

Principales métodos:

Aplicación de la catálisis de paladio dirigida electrostáticamente.
Utilizando un ligando sulfonado quiral (sSPhos) que se involucra en interacciones electrostáticas con sustratos de fenolatos a través de cationes de metales alcalinos.
Probando el dominio del ligando en varias formaciones de andamio.

Principales resultados:

Se obtuvieron espirociclohexadienonas altamente enriquecidas con antibióticos, superando las limitaciones de los métodos racémicos anteriores.
Demostró la amplia generalidad del ligando formando dos andamios previamente inaccesibles.
Sintetizó un nuevo andamio ligado al oxígeno, mostrando la versatilidad del ligando.
El ligando sSPhos demostró ser eficaz cuando se requerían ligandos quirales fundamentalmente diferentes.

Conclusiones:

El ligando quiral sulfonado sSPhos ofrece una solución ampliamente aplicable para la desaromatización arilativa del fenol.
La catálisis dirigida electrostáticamente con sSPhos simplifica la síntesis de andamios diversos y enriquecidos con enantio.
Este enfoque destaca el potencial de aprovechar las interacciones electrostáticas para la eficiencia y la generalidad catalíticas.

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