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Zirconaziridina-mediada por catalización de Ni Diastereoselectiva C (sp2) - Glicosilación

Yu Gan¹, Jun-Feng Zhou¹, Xuejiao Li¹

¹School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.

Journal of the American Chemical Society

|June 11, 2024

Resumen

Este estudio introduce una nueva catálisis de níquel mediada por zirconaziridina para la formación estereoselectiva de enlaces C-glucósidos. El método controla con precisión las configuraciones anoméricas utilizando ligandos quirales de bioxazolina (biOx) en catálisis reductiva.

Área de la Ciencia:

Síntesis orgánica
Catálisis
Química de los carbohidratos

Sus antecedentes:

La formación estereoselectiva de enlaces C-glucósidos es crucial en la síntesis orgánica.
Los ligandos quirales son esenciales para el control de la estereoquímica en la química de los carbohidratos.
Los métodos existentes se enfrentan a desafíos debido a la quiralidad inherente de los sacáridos.

Objetivo del estudio:

Desarrollar una catálisis asimétrica de níquel mediada por zirconaziridina sin precedentes.
Para lograr el acoplamiento diastereoselectivo de los fosfatos glicosílicos con varios electrófilos.
Para permitir un estereocontrol preciso sobre las dos configuraciones anómero de C ((sp2) -glicosidos.

Principales métodos:

Se utilizó la catálisis asimétrica de níquel mediada por zirconaziridina.
Se utilizan fosfatos de glucósilo estables en el laboratorio y yoduros (hetero) aromáticos/glicosílicos.
Aplicación de ligandos quirales de bioxazolina (biOx) para el control estéreo.

Principales resultados:

Estableció un nuevo sistema catalítico para la formación de enlaces C-glucósidos.
Demostrado amplio alcance y alta tolerancia del grupo funcional.
Se logró un estereocontrol preciso para ambas configuraciones anoméricas utilizando ligandos biOx.

Conclusiones:

El método desarrollado ofrece una ruta eficiente a los C-glucósidos estereodefinidos.
El sistema catalítico es versátil y ampliamente aplicable en la síntesis orgánica.
El mecanismo implica una especie bimetálica de Ni-Zr que actúa como un reductor de un solo electrón.

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