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Cicloadición enantioselectiva catalizada por el paladio de 1,4-dipolos carbonilógicos: acceso eficiente a las

Barry M Trost¹, Zhiwei Jiao¹

¹Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States.

Journal of the American Chemical Society

|December 18, 2020

Resumen

Un nuevo método utiliza el paladio para crear ciclohexanonas quirales a través de la síntesis asimétrica. Esta reacción de cicloadición catalítica ofrece una nueva ruta a valiosos compuestos orgánicos quirales.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Las reacciones mediadas por el paladio son cruciales en la síntesis orgánica.
El desarrollo de métodos de síntesis asimétricos eficientes para las ciclohexanonas quirales sigue siendo un desafío.

Objetivo del estudio:

Desarrollar un nuevo carbonio dipolar mediado por el paladio para la síntesis asimétrica.
Para aplicar este dipolo en una cicloadición catalítica [4+2] para la síntesis quiral de ciclohexanona.

Principales métodos:

Se utilizó la desprotonación in situ para generar el dipolo mediado por el paladio.
Para la inducción asimétrica se empleó un ligando de fosforamidita C2-no simétrico.
Los carbonatos alilicos con deficiencia de electrones se utilizaron como nuevos precursores de dipolo.

Principales resultados:

El método desarrollado sintetizó con éxito ciclohexanonas quirales a través de la cicloadición catalítica asimétrica [4 + 2].
Se exploró una amplia gama de precursores de dipolo estables.
Un mecanismo propuesto explica la vía de reacción y el control estereoquímico.

Conclusiones:

Este estudio presenta un método nuevo y eficiente para la síntesis asimétrica de ciclohexanonas quirales.
El dipolo mediado por paladio y el sistema catalítico desarrollado ofrecen una plataforma versátil para construir moléculas quirales complejas.
El mecanismo propuesto ayuda a comprender y predecir los resultados estereoquímicos en las transformaciones relacionadas.

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