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Libre de aditivos y metales, previsiblemente 1,2- y 1,3-regioselectiva, fotoinducida por la doble borilación C-H/C-X

Adelphe M Mfuh¹, Vu T Nguyen¹, Bhuwan Chhetri¹

¹Department of Chemistry, University of Texas at San Antonio , San Antonio, Texas 78249, United States.

Journal of the American Chemical Society

|June 28, 2016

Resumen

Este estudio introduce un nuevo método de borilación dual C-H/C-X fotoinducido para haloarenos. La reacción sintetiza eficazmente los diborilarenos en escalas de gramos, ofreciendo una vía sintética versátil.

Área de la Ciencia:

Química orgánica
La fotoquímica
Metodología sintética

Sus antecedentes:

Las reacciones de borilación catalizadas por metales son cruciales en la síntesis orgánica.
El desarrollo de métodos sin metales y sin aditivos sigue siendo un desafío importante.
Las reacciones fotoinducidas ofrecen nuevas vías para las transformaciones químicas.

Objetivo del estudio:

Desarrollar una reacción de borilación dual C-H/C-X fotoinducida simple, libre de aditivos y metales.
Para sintetizar 1,2- y 1,3-diborilarenos a partir de haloarenos fácilmente disponibles.
Investigar los factores que controlan la regioselectividad en este proceso de borilación dual.

Principales métodos:

Fotorradiación de cloro, bromo y yodoarenos en presencia de una fuente de boro.
Utilizando condiciones de lote y flujo continuo para la síntesis a escala de gramos.
Variación sistemática de disolventes y sustituyentes en las haloarenas para estudiar la regioselectividad.

Principales resultados:

Se logró una borilación dual C-H/C-X de varios haloarenos sin aditivos ni metales.
Se produjeron cantidades en escala de gramos de 1,2- y 1,3-diborilarenos.
Se descubrió que la regioselectividad depende de las propiedades del disolvente y las propiedades electrónicas/estéricas de los sustituyentes de haloareno.

Conclusiones:

Se ha establecido un método novedoso, eficiente y sostenible para la borilación dual C-H/C-X.
El protocolo desarrollado proporciona acceso a los valiosos diborilarenos en condiciones suaves y libres de metales.
La comprensión de la regioselectividad ofrece oportunidades para la síntesis específica de isómeros de diborilareno específicos.

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