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Sistemas de catalizadores ortogonales basados en Cu- y Pd para la O- y N-arilación de aminofenoles

Debabrata Maiti¹, Stephen L Buchwald

¹Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

Journal of the American Chemical Society

|November 11, 2009

Resumen

Desarrolló nuevos sistemas de catalizadores de cobre y paladio para la O- y N-arilación selectiva de aminofenoles. Estos métodos permiten la síntesis eficiente de compuestos potencialmente terapéuticos utilizando haluros de arilo.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.
La catálisis de la catálisis.

Sus antecedentes:

Los derivados de aminofenol son motivos estructurales clave en el descubrimiento de fármacos.
La arilación selectiva de los aminofenoles es crucial para la síntesis de agentes terapéuticos.
Los métodos existentes a menudo carecen de selectividad o requieren la protección de grupos.

Objetivo del estudio:

Desarrollar sistemas de catalizadores complementarios de cobre (Cu) y paladio (Pd).
Para lograr la O- y N-arilación selectiva de los aminofenoles sin protección.
Para utilizar haluros de arilo fácilmente disponibles como socios de acoplamiento.

Principales métodos:

O-arilación catalizada por cobre utilizando ácido picolínico o ligandos de CyDMEDA.
La N-arilación catalizada por paladio empleando el precatalizador BrettPhos.
La N-arilación directa del 2-aminofenol utilizando el CuI.

Principales resultados:

O-arilación selectiva de 3- y 4-aminofenoles lograda con catalizadores Cu.
N-arilación selectiva de 3- y 4-aminofenoles demostrada con el catalizador Pd.
La N-arilación selectiva del 2-aminofenol fue exitosa con CuI; la O-arilación sigue siendo un reto.
Se toleraron diferentes propiedades electrónicas y grupos funcionales en los socios de acoplamiento.

Conclusiones:

Métodos de arilación eficientes y selectivos establecidos catalizados por Cu y Pd para los aminofenoles no protegidos.
Estos sistemas catalíticos ofrecen rutas versátiles a valiosos productos de aminofenol O- y N-arilados.
Los métodos desarrollados facilitan la síntesis de posibles fármacos candidatos con diversas funcionalidades.

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