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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs

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Catálisis de Au enantioselectiva dirigida a contra-iones con enlace H

Allegra Franchino¹, Àlex Martí^1,2, Antonio M Echavarren^1,2

¹Institute of Chemical Research of Catalonia (ICIQ), Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007 Tarragona, Spain.

Journal of the American Chemical Society

|February 9, 2022

Resumen

Una nueva estrategia utiliza donantes de enlaces H en los ligandos para posicionar con precisión las contraaniones quirales para la catálisis enantioselectiva. Esto permite el primer uso general de aniones quirales en reacciones catalizadas por oro.

Área de la Ciencia:

Química organometálica
Catálisis asimétrica
Química supramolecular

Sus antecedentes:

La catálisis enantioselectiva es crucial para sintetizar moléculas quirales.
Se sabe que los contraaniones quirales inducen la asimetría, pero su uso general en la catálisis del oro es limitado.
El control preciso sobre el entorno quiral es clave para una inducción asimétrica eficiente.

Objetivo del estudio:

Desarrollar una nueva estrategia para la catálisis enantioselectiva de metales de transición utilizando donantes de enlaces H.
Demostrar la utilidad de esta estrategia en ciclizaciones catalizadas por oro de 1,6-eninos.
Para permitir la aplicación general de aniones quirales en las reacciones catalizadas por el oro.

Principales métodos:

Se utilizó un complejo de oro catiónico (I) con un ligando donante de enlace H.
Combina el complejo de oro (I) con una sal de fosforamidato de plata (I) derivada de BINOL como fuente de contraanión quiral.
Mecanismos de reacción investigados mediante titulaciones de RMN de 1H, estudios cinéticos y análisis de efectos de disolvente/no lineal.

Principales resultados:

Se han demostrado con éxito ciclizaciones enantioselectivas de 5-exo-dig y 6-endo-dig de 1,6-eninas.
Logró el primer uso general de aniones quirales en reacciones catalizadas por oro con sustratos alquinos desafiantes.
Substanció el papel crítico de las interacciones de enlace H en la dirección de la inducción asimétrica.

Conclusiones:

La estrategia dirigida por enlaces H desarrollada proporciona un nuevo paradigma para la catálisis asimétrica.
Este enfoque integra la catálisis de metales, la organocatálisis de enlaces H y la catálisis asimétrica dirigida por contraiones.
Ofrece un plan para diseñar ligandos quirales ensamblados supramolecularmente para complejos metálicos.

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