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La olefinación enantioselectiva de C-H catalizada por Pd (II) de los ácidos difenilacéticos

Bing-Feng Shi¹, Yang-Hui Zhang, Jonathan K Lam

¹Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.

Journal of the American Chemical Society

|December 19, 2009

Resumen

Los ligandos de aminoácidos quirales permiten la olefinación C-H enantioselectiva catalizada por el paladio de los ácidos difenilacéticos. Esta reacción produce productos olefinados específicos con configuraciones absolutas predecibles, confirmadas por un intermediario de inserción C-H propuesto.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis es la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

Las reacciones catalizadas por el paladio (II) son cruciales en la síntesis orgánica.
La funcionalización C-H enantioselectiva ofrece rutas sintéticas eficientes.
Los derivados del ácido difenilacético son valiosos intermediarios sintéticos.

Objetivo del estudio:

Desarrollar un método de olefinación C-H enantioselectivo para sustratos de ácido difenilacético.
Para utilizar ligandos de aminoácidos quirales monoprotegidos en la catálisis del paladio.
Para aclarar el resultado estereoquímico y el mecanismo de reacción.

Principales métodos:

Empleando el paladio (II) catalizadores.
Utilizando ligandos de aminoácidos quirales monoprotegidos.
Realización de olefinación C-H en sustratos de ácido difenilacético.

Principales resultados:

Se ha logrado con éxito la olefinación C-H enantioselectiva de sustratos de ácido difenilacético.
La reacción procedió con una alta estereoselectividad.
La configuración absoluta de los productos correlacionados con un intermediario de inserción C-H propuesto.

Conclusiones:

Los ligandos de aminoácidos quirales monoprotegidos son efectivos en la olefinación enantioselectiva de C-H catalizada por Pd (II).
El estudio proporciona un nuevo método para sintetizar compuestos olefinados quirales.
Los hallazgos apoyan un mecanismo propuesto que implica la inserción de C-H.

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