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Química orgánica. químico orgánico. Clivado de enlace C-C catalizado por Rh mediante hidroformilación por

Stephen K Murphy¹, Jung-Woo Park², Faben A Cruz²

¹Department of Chemistry, University of California Irvine, CA 92697-2025, USA. Department of Chemistry, University of Toronto, Ontario M5S 3H6, Canada.

Science (New York, N.Y.)

|January 3, 2015

Resumen

Desarrollamos un método de deshidroformilación sintética utilizando un catalizador de rodio para convertir aldehídos en olefinas. Este proceso eficiente funciona en condiciones suaves y es aplicable a la síntesis de productos naturales.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La deshidroformilación de aldehídos a olefinas es un paso clave en la biosíntesis de esteroles, incluido el colesterol.
Los métodos sintéticos existentes a menudo requieren condiciones duras o carecen de eficiencia.

Objetivo del estudio:

Desarrollar un método sintético suave y eficiente para la deshidroformilación de aldehídos a olefinas.
Para explorar la aplicación de este método en la síntesis de productos naturales.

Principales métodos:

Utilizó un catalizador de rodio (xantfos) (benzoato) para la activación del enlace C-H y la escisión del enlace C-C.
Se emplearon temperaturas de reacción suaves (2280°C) y bajas cargas de catalizador (0,32 mol%).
Investigó el mecanismo de reacción, identificando el papel del contra-ion benzoato como transporte de protones.

Principales resultados:

Se logra la deshidroformilación quimioselectiva de aldehídos a olefinas.
Demostró la aplicabilidad del protocolo a diversos productos naturales.
Se sintetizó con éxito (+) - yohimbenona en una secuencia de tres pasos.

Conclusiones:

El protocolo desarrollado catalizado por rodio ofrece una ruta eficiente y suave para la síntesis de olefinas a través de la deshidroformilación.
El mecanismo implica la transferencia de hidroformilación facilitada por el contrapartida de benzoato.
Esta metodología es prometedora para la síntesis de moléculas complejas.

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