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Fosfinas quelatantes α-dicacionarias: síntesis y aplicación a la hidroarilación de los dienos

Lianghu Gu¹, Lawrence M Wolf², Adam Zieliński¹

¹Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen , Tammannstraße 2, 37077 Göttingen, Germany.

Journal of the American Chemical Society

|March 22, 2017

Resumen

Se han sintetizado nuevos ligandos quelantes de P^P con una unidad diccionaria. Estos ligandos mejoran la acidez de Lewis del metal, lo que permite una hidroariación eficiente catalizada por el rodio de dienos con moléculas aromáticas.

Área de la Ciencia:

Química organometálica
Diseño del ligando
Catálisis

Sus antecedentes:

Los ligandos quelantes son cruciales en la química de coordinación y la catálisis.
Los fragmentos dicationicos a menudo son difíciles de incorporar en andamios de ligandos.
La acidez de Lewis de los centros metálicos dicta la actividad catalítica.

Objetivo del estudio:

Sintetizar nuevos ligandos quelantes P^P con una unidad diccionaria.
Investigar el comportamiento de coordinación y las propiedades electrónicas de estos ligandos.
Desarrollar un catalizador eficiente para las reacciones de hidroarilación.

Principales métodos:

Síntesis de nuevos ligandos quelatantes de P^P.
Estudios de reactividad con varios centros metálicos.
Pruebas catalíticas para la hidroarilación.
Estudios cinéticos y experimentos de etiquetado de deuterio.
Cálculos de la teoría funcional de la densidad (DFT).

Principales resultados:

Síntesis exitosa de ligandos quelatantes de P^P que incorporan un fragmento dicationico.
Se ha demostrado la quelación fácil y la acidez de Lewis mejorada de los metales coordinados.
Desarrolló un catalizador de rodio altamente eficiente para la hidroarilación de dieno.
Mecanismos de reacción aclarados a través de estudios cinéticos y computacionales.

Conclusiones:

Los ligandos diseñados incorporan efectivamente unidades de dicatión en andamios quelantes.
La acidez de Lewis mejorada de los metales facilita las transformaciones catalíticas desafiantes.
El catalizador de rodio desarrollado ofrece una nueva ruta para la hidroarilación.

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