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La activación fácil y altamente selectiva de C-H catalizada por nucleófilo del fluoroformo con Pd (II) es fácil y

Shin Takemoto¹, Vladimir V Grushin

¹Institute of Chemical Research of Catalonia (ICIQ) , Tarragona 43007, Spain.

Journal of the American Chemical Society

|October 31, 2013

Resumen

Este estudio presenta un método fácil para la activación de H-CF3 a temperatura ambiente, formando un enlace de paladio-trifluorometilo (Pd-CF3). Se propone un nuevo mecanismo que involucra la unión de hidrógeno y la promoción de la base de Lewis.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Química del flúor Química del flúor
La catálisis de la catálisis.

Sus antecedentes:

Las reacciones catalizadas por el paladio son cruciales en la síntesis orgánica.
Los métodos eficientes para la introducción de grupos trifluorometilo son muy buscados.
La activación de H-CF3 presenta un desafío debido al fuerte enlace C-H.

Objetivo del estudio:

Desarrollar un método fácil y quimioselectivo para la activación de H-CF3.
Para investigar el mecanismo de la formación de enlaces Pd-CF3 mediada por el paladio.
Explorar el papel de los promotores de bases de Lewis en el ciclo catalítico.

Principales métodos:

Utilizó un complejo [dppp) Pd Ph (OH) ] para la activación de H-CF3.
Empleó a n-Bu3P como promotor de la base de Lewis.
Combinó observaciones experimentales con estudios computacionales para dilucidar el mecanismo de reacción.

Principales resultados:

Se logró un rendimiento casi cuantitativo de la formación de enlaces Pd-CF3 a 23 °C.
Se ha demostrado una alta quimioselectividad en el proceso de activación de H-CF3.
Identificó un nuevo mecanismo que involucra la unión H y el ataque nucleofílico por parte del promotor.

Conclusiones:

El método desarrollado ofrece una ruta eficiente para la formación de enlaces Pd-CF3 en condiciones suaves.
El mecanismo propuesto proporciona nuevos conocimientos sobre la funcionalización C-H catalizada por el paladio.
Este trabajo facilita el desarrollo de nuevas estrategias de trifluorometilación.

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