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Acceso conveniente al espacio químico poco explorado: desoxigenado C-C acoplamiento cruzado

William L Lyon¹, David W C MacMillan¹

¹Merck Center for Catalysis at Princeton University, Princeton, New Jersey 08544, United States.

Journal of the American Chemical Society

|March 28, 2023

Resumen

Este estudio introduce un nuevo método catalizado por níquel para la formación de enlaces carbono-carbono utilizando alcoholes y bromuros de alquilo. Esta alquilación desoxigenativa se acopla eficientemente a los centros de carbono secundarios desafiantes, lo que permite la síntesis de moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los alcoholes son fuentes abundantes y diversas de carbono híbrido.
El uso directo de alcoholes en los acoplamientos cruzados formadores de enlaces C-C está poco desarrollado.
La formación de enlaces entre dos centros secundarios de carbono es un desafío sintético significativo.

Objetivo del estudio:

Desarrollar un nuevo método para la alquilación desoxigenativa de alcoholes y bromuros de alquilo.
Para permitir el acoplamiento cruzado C{\displaystyle C} -C{\displaystyle C} , particularmente entre los centros de carbono secundarios.
Para expandir la utilidad sintética de los alcoholes en la construcción de arquitecturas moleculares complejas.

Principales métodos:

Se utilizó la catálisis de níquel-metal fotorredóxido mediada por carbenos N-heterocíclicos (NHC).
Se utiliza un enfoque desoxigenativo para activar los alcoholes para el acoplamiento cruzado.
Investigó el alcance de la reacción con varios alcoholes y bromuros de alquilo.

Principales resultados:

Se logró con éxito el acoplamiento cruzado C ((sp³) -C ((sp³) entre los alcoholes y los bromuros de alquilo.
Demostrado amplio alcance del sustrato, incluida la difícil formación de enlaces entre dos carbonos secundarios.
Se mostró el acoplamiento de sistemas tridimensionales de alta tensión (espirociclos, bicicletas, anillos fundidos) y anillos farmacóforos.

Conclusiones:

Desarrolló un sistema catalítico de níquel-fotorredóxido ligado NHC versátil para la alquilación desoxigenativa.
Ha permitido la síntesis de nuevos marcos moleculares y alternativas 3D a los enlaces biarílicos.
Destacó la utilidad práctica a través de la síntesis acelerada de moléculas bioactivas.

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