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Acceso modular a las aminas quirales mediante catálisis fotoenzimática basada en la imina reductasa

Bin Chen¹, Renjie Li¹, Jianqiang Feng²

¹State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.

Journal of the American Chemical Society

|May 10, 2024

Resumen

Las iminas reductasas (IRED) se reutilizan para catalizar nuevas reacciones radicales utilizando la luz, lo que permite nuevas transformaciones asimétricas. Este descubrimiento amplía el conjunto de herramientas para crear aminas quirales complejas a través de procesos de un solo electrón fotoinducidos.

Área de la Ciencia:

Química sintética
Biocatálisis
La fotoquímica

Sus antecedentes:

El desarrollo de catalizadores es crucial para la innovación sintética.
Las enzimas reutilizadas para las fotobiotransformaciones son limitadas, principalmente las flavoproteínas y las ceto-reductasas.
Las iminas reductasas (IRED) realizan naturalmente la aminación reductora.

Objetivo del estudio:

Explorar el potencial de las iminas reductasas (IRED) en las fotobiotransformaciones nuevas en la naturaleza.
Para permitir la formación remota de enlaces C ((sp3) -C ((sp3)) a través de la hidroalquilación radical de las enamidas.
Desarrollar métodos enantioselectivos para la síntesis de aminas quirales.

Principales métodos:

Excitación directa por luz visible de los IRED diseñados.
Sinergia entre los IRED y los catalizadores fotorredóxicos sintéticos.
Experimentos mecánicos húmedos y simulaciones computacionales.

Principales resultados:

Se ha demostrado que los IRED catalizan la hidroalquilación radical de las enamidas para la síntesis de aminas quirales (45 ejemplos, hasta un 99% ee).
Los IRED reutilizados facilitan procesos radicales de un solo electrón no inducidos por la luz natural.
Los IRED diseñados dirigen efectivamente los radicales intermedios hacia vías enantioselectivas.

Conclusiones:

Los IRED se pueden aprovechar como fotoenzimas para nuevas transformaciones asimétricas.
Este enfoque proporciona un nuevo paradigma para desafiar la síntesis asimétrica.
Ofrece una alternativa prometedora a los métodos quimiocatalíticos tradicionales.

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