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Autoensamblaje jerárquico de abajo hacia arriba de las porfirinas quirales a través de la coordinación y los enlaces
Cristina Oliveras-González1, Florent Di Meo2, Arántzazu González-Campo1
1Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus Universitari de Bellaterra , 08193 Cerdanyola del Vallès, Catalonia, Spain.
Journal of the American Chemical Society
|November 24, 2015
Resumen
Los macrociclos quirales se autoensamblan en estructuras jerárquicas, exhibiendo una actividad óptica significativa debido a la organización supramolecular. Este proceso de ensamblaje, impulsado por coordinación y enlaces de hidrógeno, permite la creación de nuevos materiales moleculares.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- Síntesis orgánica
Sus antecedentes:
- Los compuestos sintéticos quirales pueden exhibir comportamientos complejos de autoensamblaje.
- Las propiedades ópticas de las moléculas están influenciadas por su estado de agregación y el entorno molecular.
- Comprender el ensamblaje jerárquico es crucial para diseñar materiales moleculares avanzados.
Objetivo del estudio:
- Para investigar el autoensamblaje jerárquico de compuestos sintéticos quirales.
- Correlacionar la estructura molecular, en particular los centros estereogénicos y los grupos funcionales, con la actividad óptica observada.
- Explorar la formación de nuevos nanomateriales a través del autoensamblaje controlado.
Principales métodos:
- Estudios de espectroscopia de absorción y dicroísmo circular dependiente de la temperatura (CD) en solución.
- Modelado molecular y cálculos de señales de CD.
- Microscopía de fuerza atómica (AFM) y microscopía electrónica de barrido (SEM) de conjuntos depositados y precipitados.
Principales resultados:
- Los macrociclos quirales se autoensamblan jerárquicamente, influenciados por la coordinación y los enlaces de hidrógeno.
- La actividad óptica de los agregados abarca dos órdenes de magnitud, significativamente mejorada en comparación con los cromóforos aislados.
- El ensamblaje jerárquico ocurre principalmente en solución, con dimensionalidad agregada dependiente de las condiciones de deposición.
- Se forman nanomateriales fibrilares, dependiendo del número y la posición de los grupos de amida quiral.
Conclusiones:
- La organización supramolecular de las moléculas quirales dicta su actividad óptica.
- El ensamblaje jerárquico impulsado por interacciones específicas (por ejemplo, zinc ((II) -piridil, enlace de hidrógeno) conduce a propiedades ópticas mejoradas.
- Este trabajo proporciona una vía para crear materiales moleculares con entornos cromóforos adaptados.
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