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Reorganizaciones catalíticas enantioselectivas del 1,2-borato

Hayden A Sharma¹, Jake Z Essman¹, Eric N Jacobsen¹

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.

Science (New York, N.Y.)

|November 4, 2021

Resumen

Este estudio introduce un reordenamiento catalítico enantioselectivo para la síntesis de ésteres borónicos quirales de α-cloro pinacol. Estos versátiles bloques de construcción permiten la creación eficiente de diversos estereocentros trisubstituidos en la síntesis orgánica.

Área de la Ciencia:

Química orgánica
Química sintética
Catálisis

Sus antecedentes:

La construcción de estereocentros trisubstituidos es crucial en la química sintética.
El desarrollo de métodos catalíticos eficientes para los bloques de construcción quirales sigue siendo un desafío clave.

Objetivo del estudio:

Descubrir un nuevo método catalítico enantioselectivo para la síntesis de ésteres borónicos de α-cloro pinacol.
Establecer una estrategia para generar diversos estereocentros trisubstituidos a partir de intermedios quirales comunes.

Principales métodos:

Reacción de reordenamiento de 1,2-boronato enantioselectiva y catalítica.
Se utilizaron como materiales de partida los ésteres borónicos y el diclorometano fácilmente disponibles.
Utilizó un complejo de litio-isotiourea-boronato como catalizador.

Principales resultados:

Se han sintetizado con éxito ésteres borónicos de α-cloro pinacol con alta enantioselectividad.
Se ha demostrado que los productos quirales pueden elaborarse en varios estereocentros trisubstituidos.
Propuso un mecanismo catalítico que involucra la abstracción de cloruro inducida por doble litio.

Conclusiones:

El reordenamiento de 1,2-boronato desarrollado ofrece una estrategia poderosa y habilitadora para los químicos sintéticos.
Este método proporciona acceso a bloques de construcción quirales valiosos para la construcción de moléculas complejas.
El sistema catalítico facilita la síntesis eficiente de diversos estereocentros trisubstituidos.

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