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Nuevas síntesis de E7389 C14-C35 y de los bloques de construcción de la halichondrina C14-C38: enfoques de

Cheng-Guo Dong¹, James A Henderson, Yosuke Kaburagi

¹Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.

Journal of the American Chemical Society

|October 8, 2009

Resumen

Este estudio presenta reacciones de acoplamiento mediadas por cromo rentables utilizando dos enfoques novedosos. Estos métodos logran una alta eficiencia y estereoselectividad en la síntesis de bloques de construcción complejos, adecuados para escalar.

Área de la Ciencia:

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

Sus antecedentes:

Las reacciones de acoplamiento mediadas por cromo generalmente requieren un exceso de nucleófilos, lo que aumenta los costos.
El desarrollo de rutas sintéticas rentables y eficientes es crucial para la síntesis de moléculas complejas.

Objetivo del estudio:

Investigar dos nuevos enfoques para reacciones de acoplamiento mediadas por cromo rentables.
Para lograr una alta eficiencia y estereoselectividad en la síntesis de bloques de construcción clave.

Principales métodos:

Dos acoplamientos catalíticos asimétricos consecutivos mediados por cromo con socios de acoplamiento desequilibrados.
Identificación de un nucleófilo específico que permita un acoplamiento de proporción molar 1:1.
Construcción estereospecífica del enlace C23-O a través de la ciclización reductora o la ciclización oxy-Michael.

Principales resultados:

Síntesis exitosa de E7389 C14-C35 y halichondrina C14-C38 bloques de construcción.
Altos rendimientos generales y una excelente estereoselectividad alcanzada en ambas rutas sintéticas.
Se ha demostrado la viabilidad de utilizar una relación molar de 1:1 para un acoplamiento eficiente.

Conclusiones:

Los métodos desarrollados ofrecen una alternativa rentable a los acoplamientos tradicionales mediados por cromo.
La simplicidad operativa hace que la síntesis sea muy adecuada para la ampliación industrial.
La síntesis eficiente de complejos fragmentos moleculares es ahora más accesible.

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