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La activación de C-C catalizada por Pt inducida por la activación de C-H
Miriam A Bowring1, Robert G Bergman, T Don Tilley
1Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|August 22, 2013
Resumen
Los catalizadores de platino (II) cortan dos enlaces carbono-carbono en un hidrocarburo, dando lugar a un nuevo producto de reordenamiento. Este estudio revela un mecanismo catalítico inusual iniciado por la activación del enlace C-H.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La escisión del enlace carbono-carbono (C-C) es una transformación fundamental en la química orgánica.
- El desarrollo de métodos catalíticos eficientes para la activación de enlaces C-C sigue siendo un desafío importante.
Objetivo del estudio:
- Para investigar la escisión catalítica de dos enlaces simples C-C en el espiro [biciclo[2.2.1]hept-2-eno-7,1'-ciclopropano].
- Para aclarar el mecanismo de esta nueva transformación catalítica utilizando platino ((II) catalizadores.
Principales métodos:
- Tratamiento del sustrato de hidrocarburos con catalizadores de platino, específicamente (Me2bpy) PtPh (NTf2).
- Caracterización del producto mediante espectroscopia de RMN y espectrometría de masas de ionización por electrospray.
- Estudios mecánicos que involucran el etiquetado de deuterio y cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- La reacción catalítica rompió con éxito dos enlaces simples C-C en el sustrato.
- Se obtuvo en buen rendimiento un sorprendente producto de reordenamiento, el 1,2,4,7,7a-pentahidroindeno.
- La evidencia apoya un mecanismo catalítico inusual que involucra la activación inicial del enlace C-H seguida de la escisión del enlace C-C.
Conclusiones:
- Los catalizadores de platino pueden mediar efectivamente la escisión de múltiples enlaces C-C en un hidrocarburo complejo.
- La reacción procede a través de un mecanismo único iniciado por la activación del enlace C-H, ofreciendo nuevos conocimientos sobre las estrategias catalíticas de activación del enlace C-C.
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