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La activación nucleofílica de los hidrosilanos a través de una estrategia de imposición de tensión que conduce a los

Toshiya Ikeuchi¹, Keiichi Hirano¹, Masanobu Uchiyama^1,2,3

¹Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.

Journal of the American Chemical Society

|March 5, 2021

Resumen

Este estudio introduce un nuevo método sin metales para la hidrosilación transselectiva de alquinos utilizando hidrosilanos cíclicos. La estrategia utiliza la tensión estérica para lograr una síntesis eficiente de compuestos cíclicos que contienen silicio.

Área de la Ciencia:

Química del silicio orgánico
Catálisis
Química orgánica sintética

Sus antecedentes:

La hidrociliación generalmente requiere catalizadores de metales de transición.
Los alquinos no activados son sustratos difíciles para la hidrociliación libre de metales.
El acceso a los heterociclos que contienen silicio a menudo implica rutas sintéticas complejas.

Objetivo del estudio:

Desarrollar un método libre de metales de transición para la hidrosilación transselectiva de alquinas no activadas.
Investigar el uso de hidrosilanos cíclicos y de tensión estérica para la actividad catalítica.
Proporcionar un acceso eficiente a diversos benzosilos, silapenales y sus ciclos relacionados.

Principales métodos:

Diseño y síntesis de hidrosilanos cíclicos estéricamente exigentes con ligandos de silicio bidentados.
Investigación de la formación de silicatos como un intermediario clave.
Optimización de las condiciones de reacción para la hidrosilación transselectiva de alquinas no activadas.

Principales resultados:

Se ha logrado la hidrosilación transselectiva de alquinas no activadas sin catalizadores de metales de transición.
Se ha demostrado que la congestión estérica en los productos intermedios de silicato facilita la transferencia de hidritos.
Sintetizó con éxito varios benzosilos, silafenalenos y otros silicales.

Conclusiones:

Los hidrosilanos cíclicos pueden mediar la hidrosilación transselectiva sin catalizadores metálicos.
La cepa estérica es una estrategia viable para promover la transferencia de hidruro en la química orgánica de silicio.
Este método ofrece una ruta eficiente a valiosos compuestos heterocíclicos que contienen silicio.

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