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Macrociclos ciclófanos tensados: impacto de la reducción progresiva del tamaño del anillo en la síntesis y la
Andrew R Bogdan1, Steven V Jerome, K N Houk
1The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|December 3, 2011
Resumen
Los investigadores sintetizaron nuevos macrociclos ciclófanos tensados, explorando el desafiante espacio químico. La energía de deformación influye en las relaciones de producto, permitiendo orientaciones únicas de grupos funcionales que no se encuentran en las moléculas no tensadas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química supramolecular de las moléculas.
- Síntesis Química La síntesis química es el proceso de síntesis química.
Sus antecedentes:
- Los macrociclos ciclófanos son importantes en la química medicinal y en la ciencia de los materiales.
- El acceso a los ciclofanos de anillo pequeño (11-14 miembros) es un desafío sintético.
- La energía de deformación tiene un impacto significativo en la estructura y propiedades macrocíclicas.
Objetivo del estudio:
- Para sintetizar y caracterizar una serie homóloga de macrociclos ciclófanos tensados (11-14 miembros).
- Para investigar la relación entre la energía de tensión del macrociclo y la distribución del producto en síntesis.
- Explorar la utilidad de estos sistemas tensos para nuevos arreglos espaciales de funcionalidad.
Principales métodos:
- Cicloadición azida-alquina catalizada por cobre (CuAAC) macrociclado en la química de flujo.
- Cristalografía de rayos X para la determinación estructural.
- Cálculo de las energías de deformación.
Principales resultados:
- Síntesis exitosa de macrociclos ciclófanos de 11 a 14 miembros.
- La relación macrociclo-dimero correlacionada con la energía de deformación calculada.
- El aumento de la tensión condujo a desviaciones significativas de las geometrías ideales.
- El ciclofano de 11 miembros representa el más pequeño reportado con un 1,4-disubstituido 1,2,3-triazol.
Conclusiones:
- La energía de deformación es un factor crítico en el control de los resultados de la macrociclización.
- Los ciclofanos forzados ofrecen orientaciones espaciales únicas de las funcionalidades químicas.
- Este trabajo define un límite para la deformación del anillo alcanzable con la metodología empleada.
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