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La vinilación alilica enantioselectiva catalizada por el iridio en la vinilación alilica catalizada por el iridio

James Y Hamilton¹, David Sarlah, Erick M Carreira

¹Eidgenössische Technische Hochschule Zürich, HCI H335, 8093 Zürich, Switzerland.

Journal of the American Chemical Society

|December 22, 2012

Resumen

Este estudio introduce la primera reacción de sustitución asimétrica catalizada por iridio utilizando trifluoroboratos de vinilo. El nuevo método sintetiza eficientemente valiosos dienos y trienos, incluidos los productos naturales, con alta enantioselectividad.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Catalización asimétrica por catálisis asimétrica.
Química orgánica sintética y orgánica.

Sus antecedentes:

Los trifluoroboratos de vinilo son reactivos sintéticos muy versátiles.
La catálisis asimétrica es crucial para sintetizar compuestos enantioméricamente puros.
Es importante desarrollar métodos eficientes para la síntesis de 1,4-dieno y trieno.

Objetivo del estudio:

Informar sobre la primera reacción de sustitución asimétrica catalizada por iridio con trifluoroboratos de vinilo.
Desarrollar un método para la síntesis enantioselectiva de 1,4-dienos y trienos.
Para demostrar la utilidad de este método para la síntesis de productos naturales.

Principales métodos:

Utilizando un complejo de iridio- ((P,olefin) como catalizador.
Reaccionan los alcoholes alilicos ramificados y racémicos con los alquenil trifluoroboratos de potasio.
Empleando condiciones de reacción de sustitución asimétricas.

Principales resultados:

Se logra una alta selectividad del sitio en la reacción de sustitución.
Se obtiene una excelente enantioselectividad, hasta un 99%.
Sintetizó con éxito varios 1,4-dienos y trienos, incluyendo (-) -nyasol y (-) -hinokiresinol.

Conclusiones:

La reacción catalizada por Ir desarrollada es la primera de su tipo con trifluoroboratos de vinilo.
Este método proporciona un acceso rápido a dienos y trienos enriquecidos enantioméricamente.
La metodología es aplicable a la síntesis de productos naturales biológicamente activos.

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