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Conocimientos experimentales y computacionales sobre la estabilización de los elementos del grupo principal de baja
Charles L B Macdonald1, Rajoshree Bandyopadhyay, Benjamin F T Cooper
1Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada. cmacd@uwindsor.ca
Journal of the American Chemical Society
|February 3, 2012
Resumen
Se estudiaron sales de estaño (II) con ligandos poliéteres. Las sales de cloruro exhiben una mayor unión al cloro de estaño y una mayor reactividad en comparación con las sales de triflato debido a los efectos electrónicos y estéricos.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Ciencia de los materiales Ciencia de los materiales.
- Química computacional es la química computacional.
Sus antecedentes:
- Los compuestos de estaño (II) son versátiles en síntesis y catálisis.
- Los ligandos de poliéter pueden estabilizar los iones metálicos a través de la quelación.
- Comprender los efectos de los ligandos en las propiedades del estaño es crucial para ajustar la reactividad.
Objetivo del estudio:
- Investigar las diferencias estructurales, electrónicas y de reactividad entre las sales de triflato de estaño (II) y las sales de cloruro complejas con ligandos poliéteres.
- Para dilucidar el papel de la estructura del ligando de poliéter y el contrión (triflato vs. cloruro) en las propiedades del estaño.
- Para correlacionar las observaciones experimentales con predicciones computacionales.
Principales métodos:
- Difracción de rayos X monocristalino para la caracterización estructural.
- Espectroscopia de Mössbauer y espectroscopia de resonancia magnética nuclear (RMN) de estado sólido para análisis electrónico y estructural.
- Voltametría cíclica para evaluar propiedades electroquímicas y reactividad.
- Teoría Funcional de Densidad (DFT) y cálculos de la teoría de la perturbación de MøllerPlesset (MP2) para conocimientos teóricos.
Principales resultados:
- La espectroscopia de Mössbauer indicó un carácter s más alto en los electrones de valencia de las sales triflatas.
- La RMN en estado sólido reveló diferencias significativas entre las sales de triflato y cloruro.
- La voltametría cíclica demostró las influencias estéricas y electrónicas de los ligandos poliéteres en las sales de triflato.
- Los cálculos proporcionaron información sobre los efectos de los ligandos y los sustituyentes sobre la estabilidad y la reactividad del estaño.
Conclusiones:
- La unión estaño-cloro es más sustancial que la unión estaño-triflato.
- El aumento de la reactividad de las sales de cloruro de estaño (II) se atribuye a las interacciones más fuertes estaño-cloro.
- La estructura del ligando de poliéter impacta significativamente el entorno electrónico y estérico alrededor del centro de estaño (II).
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