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Desarrollo de un ligando de dialquilbiarilfosfina resistente a la desactivación para la arilación catalizada por Pd

Kaibo Feng¹, Elaine Reichert Raguram¹, James R Howard²

¹Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts 02139, United States.

Journal of the American Chemical Society

|September 17, 2024

Resumen

Un nuevo catalizador de paladio con un ligando FPhos supera los desafíos en la síntesis farmacéutica. Este catalizador robusto permite reacciones eficientes de acoplamiento cruzado C-N que involucran N-heteroarenos, cruciales para el desarrollo de fármacos.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

Los N-heteroarenos son comunes en los productos farmacéuticos, pero plantean desafíos para las reacciones de acoplamiento cruzado C-N catalizadas por paladio.
La capacidad de los N-heteroarenos para coordinarse con los centros de paladio puede conducir a la desactivación del catalizador, limitando el alcance de la reacción.

Objetivo del estudio:

Desarrollar un sistema de catalizador de paladio robusto capaz de superar la desactivación del catalizador mediada por el N-heteroareno.
Permitir reacciones eficientes de acoplamiento C-N entre haluros de arilo de Lewis y aminas secundarias, incluidos los intermediarios farmacéuticos complejos.

Principales métodos:

Desarrollo de un nuevo ligando de dialquilbiarilfosfina, FPhos, para el soporte del catalizador de paladio.
Investigación del rendimiento del catalizador con varios haluros de arilo y aminas secundarias, incluidos los compuestos farmacéuticos.
Estudios mecanicistas que incluyen análisis estructural, análisis de componentes principales y cálculos de la teoría funcional de la densidad (DFT).

Principales resultados:

El catalizador de paladio soportado por FPhos demostró una alta robustez contra la interferencia de N-heteroareno.
Se logró un acoplamiento C-N eficiente con una amplia gama de sustratos, incluidas las aminas estéricamente obstaculizadas y funcionalizadas.
Se aclararon las características clave del diseño del ligando, incluida la preferencia conformacional para el isómero unido a O y el obstáculo estérico específico.

Conclusiones:

El ligando FPhos mitiga efectivamente la desactivación del catalizador por N-heteroarenos, ampliando la utilidad del acoplamiento C-N catalizado por Pd.
El sistema de catalizador desarrollado ofrece una herramienta valiosa para la síntesis de moléculas farmacéuticas complejas que contienen motivos de N-heteroareno.
La comprensión de las propiedades estructurales y electrónicas del ligando proporciona información para el diseño de futuros catalizadores para reacciones de acoplamiento cruzado desafiantes.

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