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La activación del enlace C-H del disolvente catalizado por aminas como ruta de desactivación para los catalizadores
Itzel Guerrero Rios1, Elena Novarino, Siebe van der Veer
1Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|November 6, 2009
Resumen
Las aminas terciarias aceleran la activación C-D del bromobenzeno-d(5) a través de la metátesis de enlaces sigma. Esto implica una desprotonación inicial y una reacción posterior con un catión trialquilamonio, formando un complejo sigma-arilo.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
Sus antecedentes:
- Los complejos de decametilzirconoceno son catalizadores activos.
- La activación de C-H y C-D son reacciones fundamentales en la química organometálica.
Objetivo del estudio:
- Investigar el papel de las aminas terciarias en la activación C-D del bromobenzeno-d(5) catalizado por un catión metilo de decametilzirconoceno.
- Para dilucidar el mecanismo de la acelerada reacción de metatesis de enlace sigma.
Principales métodos:
- Estudio experimental de la activación de C-D utilizando bromobenzeno-d(5) y un precursor del catión metilo del decametilzirconoceno.
- Estudios computacionales (DFT) para investigar los mecanismos de reacción.
Principales resultados:
- Las aminas terciarias aceleran significativamente la activación C-D del bromobenzeno-d.
- Los estudios computacionales indican un mecanismo que implica la desprotonación inicial por la amina dentro de la esfera de coordinación del metal.
- La reacción procede a través de la metátesis de enlaces sigma, formando un complejo sigma-arilo.
Conclusiones:
- Las aminas terciarias actúan como catalizadores o promotores en la metátesis de enlaces sigma del bromobenzeno-d ((5) por complejos de decametilzirconoceno.
- El mecanismo propuesto proporciona información sobre las reacciones de activación C-H/C-D aceleradas por aminas.
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