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Activación selectiva de B-H inducida por la foto de los nido-carboranos

Shengwen Xu¹, Hongjian Zhang¹, Jingkai Xu¹

¹State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.

Journal of the American Chemical Society

|March 10, 2024

Resumen

Los investigadores desarrollaron un nuevo método para la química de clúster de boro, lo que permite la funcionalización directa de B-H de los nidocarboranos. Esta estrategia fotoinducida crea radicales reactivos para acoplamientos selectivos B-N, B-S y B-Se, ayudando al descubrimiento de fármacos para la terapia de captura de neutrones de boro (BNCT).

Área de la Ciencia:

Química de los racimos de boro
Química orgánica sintética
Fotocatálisis

Sus antecedentes:

La activación del enlace B-H es crucial para la expansión de las aplicaciones de clúster de boro.
Los métodos existentes para la funcionalización de grupos de boro a menudo carecen de selectividad del sitio.
El desarrollo de nuevas rutas sintéticas es esencial para la química del clúster de boro.

Objetivo del estudio:

Introducir una nueva estrategia de reacción para la funcionalización B-H directa y selectiva del sitio de los nidocarboranos.
Explorar la activación fotoinducida de la jaula para la generación de productos intermedios reactivos de racimos de boro.
Para permitir la síntesis de nido-carboranos funcionalizados para posibles aplicaciones terapéuticas.

Principales métodos:

Activación de la jaula inducida por la luz de los nidocarboranos a través de la interacción no covalente de la jaula.
Transferencia de un solo electrón desde la jaula de nidocarborano a un fotocatalizador tras la irradiación con luz verde.
Espectroscopia de resonancia paramagnética de electrones (EPR) con resolución de tiempo para la detección de radicales transitorios.
Reacciones de acoplamiento B-N, B-S y B-Se en el aire.

Principales resultados:

Generación de un radical en jaula de nido-carborano transitorio mediante fotocatálisis.
Proyección directa del radical intermedio mediante EPR con resolución temporal.
Acoplamientos eficientes y selectivos de B-N, B-S y B-Se obtenidos con diversos sustratos.
Utilidad demostrada en la modificación y síntesis de fármacos candidatos BNCT en etapas avanzadas.

Conclusiones:

Se ha establecido un nuevo método fotocatalítico para la funcionalización B-H selectiva del sitio de los nidocarboranos.
El protocolo desarrollado ofrece una plataforma versátil para sintetizar grupos de boro funcionalizados.
Este enfoque es prometedor para avanzar en el descubrimiento de fármacos, particularmente para la terapia de captura de neutrones de boro (BNCT).

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