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Resolución cinética de las bencilaminas a través del acoplamiento cruzado C-H catalizado por el paladio

Kai-Jiong Xiao¹, Ling Chu¹, Gang Chen¹

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

Journal of the American Chemical Society

|June 2, 2016

Resumen

Los ligandos de ácido α-amino-O-metilhidroxámico (MPAHA) protegidos con chiral mono-N permiten el acoplamiento cruzado C-H enantioselectivo de las benzilaminas. Este método produce eficientemente benzilaminas quirales y productos orto-arilados, útiles para sintetizar moléculas bioactivas.

Área de la Ciencia:

Química orgánica
Catálisis
Química medicinal

Sus antecedentes:

La síntesis enantioselectiva es crucial para desarrollar productos farmacéuticos.
La funcionalización C-H catalizada por el paladio ofrece rutas sintéticas eficientes.
El desarrollo de nuevos ligandos para la catálisis asimétrica sigue siendo un desafío clave.

Objetivo del estudio:

Desarrollar una nueva reacción de acoplamiento cruzado C-H catalizada por Pd (II) para las benzilaminas.
Para utilizar ligandos quirales de ácido α-amino-O-metilhidroxámico (MPAHA) protegidos por mono-N para la resolución cinética.
Explorar la utilidad sintética de los productos resultantes para acceder a andamios moleculares valiosos.

Principales métodos:

Utilizando un catalizador de paladio (II) junto con ligandos quirales de MPAHA.
Utilizando benzilaminas con un grupo amino protegido por nosilo (Ns) como grupo directivo.
Ejecutar una resolución cinética para lograr una alta pureza enantiomérica de los productos.

Principales resultados:

Se ha logrado una alta pureza enantiomérica tanto para las benzilaminas quirales como para las benzilaminas orto-ariladas.
Demostró la eficacia de los ligandos MPAHA en la dirección del acoplamiento cruzado C-H.
Se ha demostrado la fácil transformación de las benzilaminas orto-ariladas en quirales 5,6-dihidrofenantridinas sustituidas.

Conclusiones:

El método desarrollado catalizado por Pd (II) proporciona una vía eficiente para el acoplamiento cruzado C-H enantioselectivo de las benzilaminas.
El uso de protección de la nariz fácilmente extraíble simplifica el proceso sintético.
La metodología permite el acceso a importantes estructuras quirales de dihidrofenantridina que se encuentran en productos naturales y compuestos bioactivos.

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