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Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

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Un acoplamiento asimétrico de electrófilo cruzado usando 'ene'-reductasas

Haigen Fu¹, Jingzhe Cao^1,2, Tianzhang Qiao¹

¹Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.

|August 11, 2022

Resumen

Este estudio introduce un nuevo método catalizado por enzimas para crear enlaces carbono-carbono entre dos moléculas diferentes. Dependiente de la flavina

Área de la Ciencia:

Química orgánica
Biocatálisis
Metodología sintética

Sus antecedentes:

La construcción asimétrica catalítica de enlaces Csp3-Csp3 es un desafío significativo en la síntesis orgánica.
Los acoplamientos electrofiles cruzados catalizados por metales (XEC) son potentes para la formación de enlaces C-C, pero el acoplamiento de electrofiles Csp3 distintos con selectividad sigue siendo difícil.

Objetivo del estudio:

Desarrollar un método Csp3-Csp3 XEC altamente quimioselectivo y enantioselectivo.
Utilización de las "ene-reductasas" dependientes de la flavina (ERED) para la formación de nuevos enlaces C-C.

Principales métodos:

El uso de "ene-reductasas" dependientes de la flavina (ERED) para catalizar Csp3-Csp3 XEC entre haluros de alquilo y nitroalcanos.
Utilizando la fotoexcitación de complejos de transferencia de carga con plantilla enzimática para permitir la reducción selectiva de haluros de alquilo.
Aprovechando la transferencia de átomos de hidrógeno controlada por enzimas (HAT) para la enantioselectividad.

Principales resultados:

Se obtiene una Csp3-Csp3 XEC altamente quimioselectiva y enantioselectiva entre haluros de alquilo y nitroalcanos.
Demostró un nuevo mecanismo de formación de enlaces C-C que involucra radicales alquilo y nitronatos.
Se informó de un mecanismo de transferencia de átomos de hidrógeno (HAT) controlado por enzimas para una alta enantioselectividad.

Conclusiones:

Las enzimas pueden abordar desafíos sintéticos de larga data utilizando nuevos mecanismos catalíticos.
Este XEC catalizado por ERED ofrece una nueva estrategia para la construcción asimétrica de enlaces Csp3-Csp3.
El método desarrollado proporciona una herramienta poderosa para sintetizar moléculas orgánicas complejas.

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