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Interacciones soluto-solvente y inducción quiral en cristales líquidos.
Giorgio Celebre1, Giuseppina De Luca, Michela Maiorino
1Dipartimento di Chimica, Università della Calabria, via P. Bucci, 87036 Rende (CS), Italy. giorgio.celebre@unical.it
Journal of the American Chemical Society
|August 18, 2005
Resumen
Los solutos quirales inducen fases colestéricas en cristales líquidos a través de interacciones intermoleculares. El sulfóxido de metilfenilo (MPS) demuestra la mano opuesta en diferentes disolventes, revelando los efectos del disolvente en la inducción quiral.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los cristales líquidos Ciencia de los cristales líquidos.
- Estudios de Quiralidad Estudios de Quiralidad
Sus antecedentes:
- La amplificación quiral en cristales líquidos surge de las interacciones intermoleculares.
- La influencia de los dopantes quirales flexibles en la quiralidad de fase es compleja, ya que implica el orden del soluto y la conformación del dopante.
- Los efectos del disolvente en la inducción quiral en cristales líquidos no se comprenden completamente.
Objetivo del estudio:
- Investigar la influencia del disolvente en la inducción quiral en cristales líquidos.
- Desenredar los efectos del disolvente en la conformación del soluto y el orden de orientación.
- Aclarar el papel del disolvente en la mediación de la transferencia de quiralidad de la molécula a la fase.
Principales métodos:
- Medidas de la potencia de torsión del sulfóxido de metilfenilo (MPS) en varios disolventes nemáticos.
- Experimentos de Resonancia Magnética Nuclear (RMN), incluidos los acoplamientos dipolares 1H-1H y 13C-1H.
- Teoría del campo molecular Modelado de la quiralidad de la interacción intermolecular.
Principales resultados:
- El sulfóxido de metilfenilo (MPS) indujo fases colestéricas con manos opuestas dependiendo del disolvente nemático.
- El análisis de RMN reveló la conformación del soluto dependiente del disolvente y el orden de orientación.
- La transferencia de quiralidad de la fase de soluto a la fase de cristal líquido está significativamente mediada por las interacciones de disolventes.
Conclusiones:
- El disolvente juega un papel crucial en la modulación de la inducción quiral en cristales líquidos.
- La flexibilidad conformacional de los dopantes quirales y su orden de orientación son factores clave influenciados por el disolvente.
- Este estudio proporciona información sobre los mecanismos moleculares de la amplificación quiral en sistemas supramoleculares.
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