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Tetrámeros cíclicos [2]pseudorotaxanos que consisten en dos varillas rígidas enhebradas a través de dos
Julien Frey1, Christian Tock, Jean-Paul Collin
1Laboratoire de Chimie Ogano-Minerale, LC3 UMR 7177 du CNRS, Universite Louis Pasteur, Institut de Chimie, 4 rue Blaise Pascal, 67070 Strasbourg Cedex, France.
Journal of the American Chemical Society
|July 26, 2008
Resumen
Los investigadores sintetizaron barras rígidas con un núcleo central de fenantrolina. El enhebrado catalizado por el cobre de estas varillas a través de macrociclos produjo un tetramero de pseudorotaxano [2] cuantitativo, confirmado por cristalografía de rayos X.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Coordinación Química de la Coordinación
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Desarrollo de nuevas arquitecturas moleculares con un control preciso sobre el autoensamblaje.
- Exploración de la síntesis con plantilla de iones metálicos para estructuras complejas.
- Diseño de ligandos coordinadores rígidos para una complejidad predecible.
Objetivo del estudio:
- Para sintetizar nuevos quelatos de bis-bidentato basados en un núcleo de 4,7-fenantrolina.
- Para investigar la reacción de roscado inducida por el cobre para la construcción [2] de tetrameros de pseudorotaxano.
- Caracterizar los ensamblajes supramoleculares resultantes y aclarar sus características estructurales.
Principales métodos:
- Síntesis de varillas rígidas variadamente sustituidas que incorporan un núcleo de 4,7-fenantrolina y grupos 2-piridil.
- Reacción de autoensamblaje con plantilla de cobre (I) con bis-macrociclos.
- Caracterización utilizando técnicas de estado de solución (por ejemplo, espectroscopia de RMN) y cristalografía de rayos X.
Principales resultados:
- Rendimiento cuantitativo del ensamblaje tetramérico de 4-cobre ((I) roscado [2]pseudorotaxano.
- Caracterización exitosa de los tetrámeros en solución, independientemente de los sustituyentes de las varillas.
- La determinación de la estructura de rayos X confirmó la naturaleza roscada y proporcionó información estructural detallada.
Conclusiones:
- La estrategia sintética descrita proporciona un método robusto para la construcción de arquitecturas complejas [2]pseudorotaxane.
- La reacción de roscado inducida por el cobre es altamente eficiente y general para estos quelatos bis-bidentados.
- Los datos estructurales obtenidos mejoran la comprensión del reconocimiento molecular y el autoensamblaje en la química supramolecular.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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