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Generación oxidativa de radicales centrados en el boro en los carboranos
Harrison A Mills1, Joshua L Martin1, Arnold L Rheingold2
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
|February 20, 2020
Resumen
Los investigadores generaron radicales de carboranilo centrados en el vértice de boro a través de la oxidación del precursor. Estos nuevos radicales permiten nuevas reacciones de sustitución en carboranos, creando diversos compuestos que contienen boro.
Área de la Ciencia:
- Química organometálica
- Química del boro
- La Química Radical
Sus antecedentes:
- Los carboranos son grupos de boro en forma de jaula con propiedades electrónicas únicas.
- La funcionalización de los carboranos es crucial para el desarrollo de nuevos materiales y catalizadores.
- Los métodos directos de funcionalización basados en radicales para los carboranos siguen siendo limitados.
Objetivo del estudio:
- Informar sobre la observación indirecta y la utilización de radicales de carboranilo centrados en los vértices de boro.
- Establecer un nuevo método para la funcionalización del carborano a través de radicales intermedios.
- Para explorar la reactividad de estos radicales con varios sustratos.
Principales métodos:
- Generación de radicales de carboranilo mediante la oxidación de los precursores de carboranilo modificados.
- La oxidación se dirige a un enlace B-B entre la jaula de clúster de boro y un sustituto exopolíedrico.
- Caracterización in situ y reacción de las especies radicales generadas.
Principales resultados:
- Observación indirecta exitosa y uso de radicales de carboranilo centrados en los vértices de boro.
- Se ha demostrado la reactividad de los radicales con radicales basados en oxígeno, dicalcogenuros y heterociclos N.
- Carboranos sustituidos sintetizados con nuevos enlaces B-O, B-S, B-Se, B-Te y B-C.
- Logró una química de sustitución fácil en los vértices B-H ricos en electrones y pobres en electrones.
Conclusiones:
- La oxidación de los precursores de carboranilo proporciona acceso a los radicales reactivos intermedios.
- Estos radicales de carboranilo ofrecen una plataforma versátil para la funcionalización del carborano.
- El método desarrollado es aplicable a diversos entornos electrónicos de vértices de carborano.
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