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The Synthesis of [Sn10(Si(SiMe3)3)4]2- Using a Metastable Sn(I) Halide Solution Synthesized via a Co-condensation Technique
Published on: November 28, 2016
Investigación del sistema de reducción de [Sm{N}{SiMe{3)}{2}{2}] en el THF. Estudio de la tasa y de los mecanismos
Edamana Prasad1, Brian W Knettle, Robert A Flowers
1Contribution from the Department of Chemistry and Biochemistry, Texas Tech University, Box 41061, Lubbock, Texas 79409-1061.
Journal of the American Chemical Society
|December 6, 2002
Resumen
El nuevo complejo de samario [Sm(N(SiMe(3)) ((2)) ((2)) ] reduce eficientemente los yoduros de alquilo y las cetonas. Su estructura única facilita tasas de reacción más rápidas y sugiere un mecanismo de transferencia de electrones más interno en comparación con los reductores de samario tradicionales.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química Redox Química de las redox.
- Mecanismos de reacción Mecanismos de reacción
Sus antecedentes:
- El diioduro de samario (SmI2) es un potente reductor de un solo electrón ampliamente utilizado en la síntesis orgánica.
- La hexametilfosforamida (HMPA) se usa a menudo como aditivo para mejorar la reactividad de SmI2.
- La exploración de nuevos complejos de samario puede ofrecer reactividad alternativa y conocimientos mecanicistas.
Objetivo del estudio:
- Para investigar las propiedades electroquímicas y de reactividad del complejo de samario [Sm(N(SiMe3)2) 2).
- Para determinar las constantes de velocidad y parámetros de activación para la reducción de varios sustratos.
- Para comparar el mecanismo de transferencia de electrones de [Sm(N(SiMe3)2)2] con los reductores basados en SmI2.
Principales métodos:
- Se empleó voltametría cíclica y espectroscopia UV-vis para caracterizar el reductor.
- Se utilizaron experimentos de desintegración de absorción de flujo detenido en THF para medir la cinética de la reacción.
- Se analizaron los datos cinéticos para determinar las constantes de velocidad y los parámetros de activación.
Principales resultados:
- Se encontró que el potencial redox de [Sm(N(SiMe3)2)2] es intermedio entre SmI2 y SmI2-HMPA.
- Este complejo exhibió tasas de reducción más rápidas para los yoduros de alquilo y las cetonas que el SmI2-HMPA.
- Los datos de activación indicaron estados de transición altamente ordenados con bajas barreras de activación.
Conclusiones:
- El mecanismo de reducción de los yoduros de alquilo y las cetonas por [Sm(N(SiMe3)2)2] implica más carácter de esfera interna.
- Este desplazamiento mecanicista se atribuye a las características estructurales únicas del complejo [Sm(N(SiMe3)2) 2].
- Los hallazgos destacan el potencial de los nuevos complejos de samario como reductores sintonizables en la síntesis orgánica.
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