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Agrupaciones de oro sigmoidal estructuralmente bien definidas: sondeando la correlación entre el arreglo de los
Xin He1, Yuechao Wang2, Hong Jiang2
1The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University , Beijing 100084, China.
Journal of the American Chemical Society
|April 13, 2016
Resumen
Los investigadores crearon nanocúmulos quirales de oro y oro-plata utilizando la transferencia de quiralidad de los ligandos. Estos grupos exhiben fuertes respuestas de dicroísmo circular (CD), que ofrecen nuevas posibilidades para catalizadores quirales y dispositivos quirópticos.
Área de la Ciencia:
- * Ciencias de los materiales
- * La nanotecnología
- * Química supramolecular
Sus antecedentes:
- * La disposición asimétrica de los átomos metálicos es clave para comprender la quiralidad en los nanocúmulos metálicos.
- * Los nanocúmulos quirales son vitales para el desarrollo de catalizadores quirales avanzados y dispositivos quirópticos.
Objetivo del estudio:
- * Construir grupos asimétricos de oro y oro-plata mediante la transferencia de quiralidad.
- * Investigar la relación entre la disposición de los átomos de metal y las propiedades quirópticas.
Principales métodos:
- * Transferencia de quiralidad desde los ligandos diimido.
- * Síntesis de grupos asimétricos de oro y oro-plata.
- * Cristalografía de rayos X para la caracterización estructural.
- * Cálculos de la teoría funcional de la densidad dependiente del tiempo (DFT).
Principales resultados:
- Se han sintetizado con éxito cuatro grupos asimétricos de oro y oro-plata.
- * Los cúmulos mostraron un fuerte dicroísmo circular (CD) con altos factores de anisotropía (hasta 6 × 10−3).
- * Los arreglos sigmoidales y inverso sigmoidales de los átomos de metal condujeron a efectos de algodón opuestos.
- * Las propiedades quirópticas se regían principalmente por la disposición asimétrica de los átomos metálicos.
Conclusiones:
- * La transferencia de quiralidad de los ligandos diimido permite la creación de nanocúmulos metálicos asimétricos.
- * La disposición asimétrica de los átomos de metal dicta la respuesta quiróptica.
- * Este trabajo proporciona una vía para el diseño de superficies quirales sintonizables en nanoclusters para aplicaciones avanzadas.
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