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El silicio forma una rica diversidad de complejos poliólicos alifáticos en solución acuosa
Bradley M Vis1, Jiali Wen1, Soren K Mellerup1
1Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B 5E1, Canada.
Journal of the American Chemical Society
|April 22, 2020
Resumen
Los alditoles y los ácidos aldónicos forman complejos de silicio (Si) en el agua. Los complejos de silicio hipercoordinados pueden formarse sin un grupo threo, desafiando suposiciones anteriores y revelando diversas estructuras de coordinación de Si.
Área de la Ciencia:
- Química inorgánica
- Química supramolecular
- La bioquímica
Sus antecedentes:
- La complejación del silicio (Si) en soluciones acuosas es crucial para los procesos biológicos y geoquímicos.
- El entendimiento previo sugería un requisito para arreglos específicos de grupos hidroxilo (threo) para la formación de complejos de Si hipercoordinados.
Objetivo del estudio:
- Investigar la complejación del silicio acuoso por alditoles y ácidos aldónicos.
- Elucidar la diversidad estructural y las condiciones de formación de las especies de silicio hipercoordinadas.
Principales métodos:
- Espectroscopia de resonancia magnética nuclear (RMN) de 29Si de alta sensibilidad que utiliza soluciones enriquecidas isotópicamente.
- Modelado teórico computacional para analizar estructuras e interacciones complejas.
Principales resultados:
- Se estableció que los polioles alifáticos no requieren una disposición de grupos threohydroxyl para formar complejos de Si hipercoordinados.
- Identificó trece conjuntos moleculares distintos con centros de Si de 4, 5 o 6 coordenadas.
- Se detectaron concentraciones significativas de complejos de Si bis-ligando de 5 coordenadas en condiciones biológicamente relevantes.
Conclusiones:
- La formación de complejos de silicio hipercoordinados es más versátil de lo que se pensaba anteriormente.
- La presencia de un grupo threo mejora las constantes de formación, pero no es esencial para la complejación.
- Existen diversos entornos de coordinación de silicio en soluciones acuosas con polioles, incluidos los biológicamente relevantes.
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