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La catálisis cooperativa de hidrógeno-enlace-donante con cloruro de hidrógeno permite reacciones de ciclización de

Dennis A Kutateladze¹, Eric N Jacobsen¹

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.

Journal of the American Chemical Society

|November 23, 2021

Resumen

Este estudio introduce un nuevo método de catálisis cooperativa utilizando cloruro de hidrógeno (HCl) y donantes quirales de doble enlace de hidrógeno (HBD) para la ciclización de Prins altamente enantioselectiva. Este enfoque acelera significativamente las reacciones y mejora la selectividad en condiciones ácidas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

La ciclización de Prins es una reacción clave en la síntesis orgánica.
El logro de una alta enantioselectividad en reacciones catalizadas por ácido sigue siendo un desafío.
El desarrollo de catalizadores robustos para medios fuertemente ácidos es crucial.

Objetivo del estudio:

Desarrollar un sistema de catálisis asimétrico cooperativo para la ciclización de Prins.
Investigar el uso de cloruro de hidrógeno (HCl) y donantes quirales de doble enlace de hidrógeno (HBD).
Para lograr una alta enantioselectividad en las reacciones que involucran aldehídos de alquenilo simples.

Principales métodos:

Catálisis asimétrica cooperativa que emplea HCl y HBDs quirales.
Diseño de catalizadores quirales estables bajo condiciones fuertemente ácidas.
Aplicación a una amplia gama de aldehídos de alquenilo simples.

Principales resultados:

Aplicación exitosa de la catálisis cooperativa a la ciclización de Prins altamente enantioselectiva.
Los catalizadores quirales óptimos demostraron estabilidad en condiciones ácidas.
Se observaron aceleraciones de velocidad de hasta dos órdenes de magnitud en comparación con HCl solo.

Conclusiones:

La combinación de ácidos minerales fuertes y HBDs quirales es eficaz para la ciclización de Prins enantioselectiva.
Esta estrategia de catálisis cooperativa ofrece un enfoque general para las reacciones enantioselectivas mediadas por ácido.
Los catalizadores desarrollados son robustos y eficientes en condiciones de reacción exigentes.

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