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Synthesis and Reaction Chemistry of Nanosize Monosodium Titanate
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Homólisis del enlace oxígeno-oxígeno en un nuevo complejo de alquilperóxido de titanio (IV), Cp2Ti (OOtBu) Cl
Antonio G DiPasquale1, Werner Kaminsky, James M Mayer
1Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, USA.
Journal of the American Chemical Society
|December 6, 2002
Resumen
Se sintetizó un nuevo complejo de peróxido de titanio, Cp2Ti(OOtBu) Cl, y se descubrió que se somete a una homólisis inesperada de enlaces O-O. Esta vía de descomposición genera radicales tert-butoxilo, un hallazgo sorprendente para un centro de d0 titanio (IV).
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química Inorgánica La química inorgánica es la química inorgánica.
- Mecanismos de reacción Mecanismos de reacción
Sus antecedentes:
- Los complejos de peróxido de titanio son catalizadores conocidos para las reacciones de oxidación.
- Estudios previos sobre los complejos de peróxido metálico a menudo involucran procesos redox centrados en el metal que facilitan la escisión de enlaces O-O.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo de peróxido de titanio.
- Investigar la reactividad y la ruta de descomposición del nuevo complejo, particularmente en lo que respecta a la transferencia de átomos de oxígeno y la escisión de enlaces O-O.
Principales métodos:
- Síntesis de Cp2Ti(OOtBu) Cl a partir de Cp2TiCl2 y NaOOtBu.Cl2 y también de NaOOtBu.
- Caracterización del complejo en solución y estado sólido utilizando técnicas espectroscópicas y cristalográficas.
- Estudios de reactividad con olefinas y fosfinas para sondear las vías de transferencia y descomposición de oxígeno.
Principales resultados:
- El nuevo complejo de peróxido de titanio Cp2Ti(OOtBu) Cl fue sintetizado y caracterizado con éxito.
- El complejo exhibió una inesperada falta de reactividad hacia la transferencia directa de átomos de oxígeno a olefinas y fosfinas.
- La descomposición se produjo a través de la homólisis del enlace O-O del peróxido, generando radicales tert-butoxilo, una vía no observada previamente para los centros d0 Ti(IV) sin oxidación de metales.
Conclusiones:
- La homólisis del enlace O-O en Cp2Ti(OOtBu) Cl representa un nuevo mecanismo de descomposición para los complejos de peróxido de titanio.
- La generación de radicales tert-butoxilo a partir de un centro d0 Ti ((IV) desafía los paradigmas existentes de la reactividad del peróxido metálico.
- Este hallazgo abre nuevas vías para comprender la generación de radicales a partir de peróxidos organometálicos.
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