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Caracterización estructural y reactividad a la oxidación de un complejo de níquel (II) acilperoxo
Jun Nakazawa1, Shota Terada, Masaki Yamada
1Department of Material and Life Chemistry, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama 221-8686, Japan. jnaka@kanagawa-u.ac.jp
Journal of the American Chemical Society
|April 16, 2013
Resumen
Este estudio detalla un nuevo complejo de níquel ((II) - acilperoxo, [Ni ((Tp ((CF3Me)) ((κ ((2) -mCPBA) ], que demuestra su capacidad para la oxigenación electrofílica de sulfuros y olefinas, y la abstracción de átomos H de los hidrocarburos.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
Sus antecedentes:
- Los complejos de níquel son catalizadores versátiles en la síntesis orgánica.
- Los ligandos acilperoxo pueden mediar en las reacciones de oxidación.
- La comprensión de los mecanismos de reacción es crucial para el diseño de catalizadores.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo de níquel (II) - acilperoxo.
- Para investigar la oxigenación y las capacidades de abstracción de átomos H del complejo.
- Para dilucidar la cinética y los mecanismos de reacción.
Principales métodos:
- Aislamiento y caracterización completa del complejo níquel-acilperóxido.
- Reacciones electrofílicas de oxigenación con sulfuros y olefinas.
- Reacciones de abstracción de átomo de hidrógeno con hidrocarburos.
- Estudios cinéticos (Michaelis-Menten, cinética de segundo orden).
Principales resultados:
- Se sintetizó y caracterizó con éxito el complejo níquel ((II) - acilperoxo [Ni ((Tp ((CF3Me)) ((κ ((2) -mCPBA) ].
- El complejo exhibe oxigenación electrofílica de sulfuros y olefinas, con cinética de Michaelis-Menten para el tioanisole.
- También muestra la capacidad de abstracción del átomo H para enlaces C-H activados, siguiendo la cinética de segundo orden.
- La evidencia sugiere una vía alternativa que involucra un intermediario O-O-clivado para hidrocarburos menos reactivos.
Conclusiones:
- El nuevo complejo de níquel ((II) - acilperoxo es un oxidante eficaz para varios sustratos orgánicos.
- Los mecanismos de reacción varían dependiendo de la reactividad del sustrato, involucrando tanto complejos intactos como intermediarios O-O-clivados.
- Este trabajo amplía el alcance de las reacciones de oxidación catalizadas por níquel.
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