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Catálisis asimétrica de enlace de pnictógeno: hidrogenación de transferencia por un antimonio quiral

Jian Zhang^1,2, Jun Wei², Wei-Yi Ding²

¹School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.

Journal of the American Chemical Society

|April 27, 2021

Resumen

Este estudio introduce un nuevo catalizador quiral de antimonio para la catálisis asimétrica de unión de pnictógeno. El nuevo catalizador promueve eficientemente la hidrogenación de transferencia enantioselectiva de las benzoxazinas con alto estereocontrol.

Área de la Ciencia:

Química organometálica
Catálisis asimétrica
Química supramolecular

Sus antecedentes:

El enlace de pnictógeno, utilizando interacciones σ-agujero, es un área emergente en la química sintética.
La catálisis asimétrica es crucial para sintetizar compuestos enantioméricamente puros.

Objetivo del estudio:

Demostrar el concepto de catálisis asimétrica de unión de pnictógeno.
Desarrollar un nuevo catalizador quiral de antimonio para la hidrogenación de transferencia enantioselectiva.

Principales métodos:

Síntesis de un catalizador de par catión/anión quiral de antimonio.
Hidrogenación de transferencia enantioselectiva de las benzoxazinas.
Caracterización del catalizador mediante estudios de efecto no lineal, RMN de 1H y LC-MS.

Principales resultados:

El nuevo catalizador quiral de antimonio catalizó eficientemente la hidrogenación de transferencia enantioselectiva de las benzoxazinas.
Se logró una notable eficiencia y control de enantio incluso con una baja carga de catalizador (0,05 mol %).
La biblioteca de catalizadores fue sintetizada rápidamente a partir de análogos de triarilstibina y ácido mandelico.

Conclusiones:

Este trabajo establece una prueba de concepto para la catálisis asimétrica de unión de pnictógeno.
El catalizador de antimonio quiral desarrollado ofrece una nueva herramienta prometedora para la síntesis asimétrica.
Otras investigaciones mecanicistas proporcionaron información sobre el proceso catalítico.

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