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Au(I) - Cicloisomerizaciones catalizadas terminadas por la inserción del enlace C-H sp(3)

Yoshikazu Horino¹, Takuya Yamamoto, Kohki Ueda

¹Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan. horino@eng.u-toyama.ac.jp

Journal of the American Chemical Society

|February 12, 2009

Resumen

Los catalizadores Gold (I) facilitan la cicloisomerización de las eninas y los alilalenos en complejas estructuras tetraciclicas. Este proceso implica un mecanismo de inserción C-H único, confirmado por estudios de etiquetado de deuterio.

Área de la Ciencia:

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

Sus antecedentes:

Los complejos de oro ((I) son catalizadores efectivos para diversas transformaciones orgánicas.
Las reacciones de cicloisomerización ofrecen rutas eficientes para arquitecturas moleculares complejas.

Objetivo del estudio:

Para investigar la cicloisomerización catalizada por oro de 1,5-eninas y 1,4-alilalenos.
Para dilucidar el mecanismo de la formación de adductos tetraciclicos, incluido el paso de funcionalización C-H.

Principales métodos:

Reacciones de cicloisomerización catalizadas por el oro ((I).
Experimentos de etiquetado con deuterio.
Estudios mecanicistas que involucran a los intermediarios carbenoides.

Principales resultados:

Síntesis de los derivados de tetraciclododecano y tetraciclotridecano a partir de 1,5-eninas y 1,4-alilalenos, respectivamente.
Identificación de un intermediario carbenoide estabilizado con oro.
Demostración de un mecanismo formal de inserción de C-H.

Conclusiones:

El estudio informa de una nueva vía de cicloisomerización catalizada por el oro.
El etiquetado de deuterio reveló un efecto de isótopo cinético inverso en el paso de funcionalización C-H, proporcionando información sobre el mecanismo de reacción.

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