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Reorganizaciones reductoras y enantioselectivas catalíticas de Eschenmoser-Claisen

Guoting Zhang¹, Matthew D Wodrich², Nicolai Cramer¹

¹Laboratory of Asymmetric Catalysis and Synthesis, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.

Science (New York, N.Y.)

|January 25, 2024

Resumen

La síntesis de centros de carbono congestionados es un desafío. Este estudio introduce un nuevo método catalítico para la síntesis enantioselectiva de moléculas complejas, controlando la estereoquímica en la formación de enlaces carbono-carbono.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis estereoselectiva

Sus antecedentes:

La síntesis de estereocentros cuaternarios de todo carbono congestionados es un desafío significativo en la catálisis enantioselectiva.
Las reacciones pericíclicas como los reordenamientos [3,3]-sigmatrópicos ofrecen potencial pero son difíciles de controlar enantioselectivamente.
El desarrollo de métodos catalíticos eficientes para estas transformaciones es crucial para acceder a arquitecturas moleculares complejas.

Objetivo del estudio:

Desarrollar una nueva estrategia catalítica enantioselectiva para la construcción de estereocentros cuaternarios de carbono.
Para explorar la utilidad de los hidratos quirales de 1,3,2-diazafosfoleno en la catalización de reacciones pericíclicas difíciles.
Para lograr un control preciso de los centros estereogénicos recién formados en las amidas.

Principales métodos:

El reordenamiento reductor enantioselectivo de Eschenmoser-Claisen.
Utilizando catalizadores quirales de 1,3,2-diazafosfoleno-hidruro.
Análisis de los resultados estereoquímicos y control.

Principales resultados:

Desarrollo exitoso de un reordenamiento reductor enantioselectivo de Eschenmoser-Claisen.
Control demostrado sobre dos centros estereogénicos acíclicos recién formados.
Síntesis de amidas con átomos de carbono cuaternario-terciario o cuaternario-cuaternario vecinos.

Conclusiones:

Los hidratos de 1,3,2-diafosfoleno quiral son catalizadores efectivos para las reorganizaciones enantioselectivas [3,3]-sigmatrópicas.
El método desarrollado proporciona una nueva y poderosa vía para sintetizar estereocentros cuaternarios de carbono estérico.
Este trabajo avanza en el campo de la catálisis asimétrica y la síntesis de moléculas complejas.

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