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La trans-ciclohexano-1,2-diamina es un débil director de la helicidad absoluta en los complejos quirales
Zhenzhen Dong1, Glenn P A Yap, Joseph M Fox
1Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Journal of the American Chemical Society
|September 1, 2007
Resumen
Los foldameres quirales de níquel-salina se convierten entre sí de forma helicoidal, revelando la quiralidad central.
Área de la Ciencia:
- Coordinación Química de la Coordinación
- Química supramolecular de las moléculas.
- La catálisis asimétrica.
Sus antecedentes:
- Los complejos níquel-saleno son conocidos por sus propiedades catalíticas.
- Los Foldamers ofrecen un control estructural único en el ensamblaje molecular.
- Comprender el plegamiento helicoidal es crucial para el diseño de nuevos catalizadores.
Objetivo del estudio:
- Para investigar la interconversión helicoidal de los foldamers basados en níquel-saleno.
- Para cuantificar la influencia de la quiralidad central en la helicidad del foldamer.
- Evaluar el papel del trans-ciclohexano-1,2-diamina en la dirección de la helicidad absoluta.
Principales métodos:
- Espectroscopia de Resonancia Magnética Nuclear (RMN) para observar los procesos dinámicos.
- Síntesis de foldameres basados en níquel-salina con diferentes elementos quirales.
- Análisis de las tasas de interconversión diastereomérica.
Principales resultados:
- Los diastereómeros helicoidales de los foldameros de níquel-salina se interconvierten en la escala de tiempo de la RMN.
- trans-ciclohexano-1,2-diamina es un débil director de la helicidad absoluta en estos foldameres.
- Se obtuvieron datos cuantitativos sobre la propensión de los elementos quirales a controlar el sentido de plegado.
Conclusiones:
- El estudio proporciona información sobre los factores que rigen la helicidad en los sistemas de foldamer.
- Los hallazgos tienen implicaciones para el diseño racional de catalizadores quirales.
- La débil capacidad de dirección de un componente quiral común fue inesperada.
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