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Interruptor de quiralidad inducido por solvente reversible en la estructura de atrano: control del movimiento
Alexandre Martinez1, Laure Guy, Jean-Pierre Dutasta
1Laboratoire de Chimie, CNRS, École Normale Supérieure de Lyon, 46 Allée d'Italie, F-69364 Lyon, France. alexandre.martinez@ens-lyon.fr
Journal of the American Chemical Society
|June 12, 2010
Resumen
Las jaulas moleculares atráneo-hemicriptofano muestran cambios reversibles de quiralidad controlados por solventes. Este descubrimiento permite un nuevo método para estimular los interruptores moleculares, ofreciendo un control único sobre el movimiento molecular.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Química orgánica es la química orgánica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Las jaulas moleculares atráneo-hemicriptofano poseen una quiralidad inherente debido a sus unidades de ciclotriveratrileno y grupos de éter quiral.
- La disposición Δ/Λ de la porción atrane introduce disimetría local a través de una estructura helicoidal conformacionalmente restringida.
Objetivo del estudio:
- Para demostrar que las jaulas moleculares de atrano-hemicriptofano exhiben cambios de quiralidad reversibles controlados por disolventes.
- Para establecer un nuevo modo de estimulación para interruptores moleculares basados en atrano.
Principales métodos:
- Síntesis y caracterización de complejos de oxidovanadio (V) de moléculas de hemicriptofano.
- Espectroscopia de resonancia magnética nuclear de protones (RMN) para estudiar el proceso de interconversión Δ Λ.
- Manipulación de disolventes utilizando cloroformo-d (CDCl) y benceno-d) para inducir la inversión de quiralidad.
Principales resultados:
- El estudio observó mezclas diastereoméricas que surgen de la manipulación de la unidad de ciclotriveratrileno y los grupos de éter quiral.
- Se descubrió que la elección del disolvente influye profundamente en el sentido de quiralidad del movimiento de la hélice.
- La alternancia de disolventes entre CDCl ((3) y C ((6) D ((6) indujo una inversión de quiralidad reversible.
Conclusiones:
- El disolvente juega un papel crucial en la dirección del movimiento de rotación de la porción de vanatrano, controlando el sentido de la hélice.
- Los interruptores moleculares basados en atrano pueden ser estimulados y controlados por cambios de quiralidad inducidos por solventes.
- Este trabajo establece un método novedoso y factible para controlar la quiralidad molecular utilizando estímulos externos.
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