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Cage-Walking: Diferenciación de vértices por isomerización catalizada por el paladio de B(9)-bromo-meta-carborano

Rafal M Dziedzic¹, Joshua L Martin¹, Jonathan C Axtell¹

¹Department of Chemistry and Biochemistry, University of California, Los Angeles , 607 Charles E. Young Drive East, Los Angeles, California 90095, United States.

Journal of the American Chemical Society

|May 26, 2017

Resumen

Descubrimos una nueva isomerización catalizada por el paladio de los bromo-meta-carboranos. Este proceso permite la introducción de grupos funcionales en todos los vértices de boro, particularmente en la posición B.

Área de la Ciencia:

Química organometálica
Química de los carboranos
Catálisis

Sus antecedentes:

Las reacciones de acoplamiento cruzado catalizadas por el paladio son vitales en la síntesis orgánica.
Los carboranos son compuestos de jaula únicos que contienen boro con diversas aplicaciones.
El control de la regioselectividad en la funcionalización de los carboranos sigue siendo un desafío importante.

Objetivo del estudio:

Investigar el mecanismo de las reacciones catalizadas por el paladio que involucran bromo-meta-carboranos.
Explorar la posibilidad de isomerización durante las reacciones de acoplamiento cruzado.
Desarrollar un método para la funcionalización selectiva de las jaulas de metacarborano.

Principales métodos:

Utilizó reacciones de acoplamiento cruzado catalizadas por paladio con B(9)-bromo-meta-carborano.
Se han empleado técnicas experimentales y estudios teóricos (química computacional).
Investigó la influencia de los factores estéricos en el proceso catalítico.

Principales resultados:

Observado y caracterizado el primer caso de catálisis de paladio

Conclusiones:

La isomerización "cage-walking" observada es un paso clave en la funcionalización de los carboranos.
El obstáculo estérico alrededor del catalizador de paladio juega un papel crucial en el mecanismo de isomerización.
Esta metodología ofrece una nueva ruta para la funcionalización selectiva de los metacarboranos B(2) a partir del B(9)-bromo-metacarborano.

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