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Divinilación reductora enantioselectiva de alquenos no activados por reacción de acoplamiento de ciclización

Jin-Bao Qiao¹, Ya-Qian Zhang¹, Qi-Wei Yao¹

¹State Key Laboratory of Applied Organic Chemistry (SKLAOC), College of Chemistry and Chemical Engineering, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, China.

Journal of the American Chemical Society

|August 12, 2021

Resumen

Este estudio introduce una nueva reacción de divinilación enantioselectiva para los 2-bromo-1,6-dienos no aromáticos. Este método crea nuevas arquitecturas cíclicas quirales que se encuentran en compuestos biológicamente activos.

Área de la Ciencia:

Química orgánica
Catálisis asimétrica
Metodología sintética

Sus antecedentes:

La dicarbofuncionalización asimétrica catalítica es clave para las moléculas cíclicas quirales.
Los métodos actuales a menudo usan alquenos atados al arilo, lo que limita el acceso a los compuestos fusionados con benceno.

Objetivo del estudio:

Desarrollar una divinilación electrofílica cruzada enantioselectiva de 2-bromo-1,6-dienos no aromáticos.
Para acceder a nuevas arquitecturas cíclicas quirales relevantes para los compuestos biológicamente activos.

Principales métodos:

Utilizó una estrategia de divinilación catalítica asimétrica de electrófilo cruzado.
Se utilizan los ligandos quirales tert-butilo-proximales de la methoxazolina (t-Bu-pmrox) y la 3,5-difluoropiroxidina (3,5-difluoropirox).
Realizó la reacción en condiciones suaves.

Principales resultados:

Se obtiene una alta quimio, regio y enantioselectividad en la divinilación de 2-bromo-1,6-dienes.
Con éxito sintetizó nuevas arquitecturas cíclicas quirales a partir de precursores no aromáticos.
Aplicabilidad demostrada para la incorporación de heterociclos y carbociclos quirales.

Conclusiones:

El método desarrollado proporciona una ruta versátil a diversos compuestos cíclicos quirales.
Este enfoque expande el alcance de la dicarbofuncionalización asimétrica catalítica más allá de los sustratos atados al arilo.
Permite la síntesis de moléculas complejas con valiosos motivos quirales.

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