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Ajuste de ensamblaje polimérico supramolecular a través de interacciones estéreoelectrónicas
Will R Henderson1, Guancen Liu1, Khalil A Abboud1
1George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States.
Journal of the American Chemical Society
|August 4, 2021
Resumen
La polimerización supramolecular de los nuevos ditos[3.3]paraciclfanos se logra a través del enlace de hidrógeno de amida. La oxidación del azufre a la sulfona mejora las interacciones orbitales, impulsando el ensamblaje y el alargamiento del polímero.
Área de la Ciencia:
- Química supramolecular
- Química orgánica
- Ciencias de los materiales
Sus antecedentes:
- La polimerización supramolecular ofrece una ruta a nuevos materiales con propiedades sintonizables.
- El enlace de hidrógeno es una interacción no covalente clave que impulsa el autoensamblaje.
- Los paraciclopanos proporcionan andamios estructurales únicos para el diseño molecular.
Objetivo del estudio:
- Para investigar la polimerización supramolecular de 2,11-ditía [3.3] paraciclfanos.
- Para aclarar el papel de la unión de hidrógeno de amida intermolecular y transanular en la conducción de la polimerización.
- Explorar el impacto de los efectos estereoelectrónicos, específicamente las interacciones n → π *, en el ensamblaje de polímeros.
Principales métodos:
- Síntesis y caracterización de las 2,11-dithia[3.3]paraciclophanas.
- Análisis espectroscópico (NMR, IR) para estudiar el enlace de hidrógeno y la polimerización.
- Cristalografía de rayos X para determinar los cambios estructurales.
- Química computacional (DFT) para investigar las interacciones electrónicas y los sistemas de modelos.
Principales resultados:
- Exitosa polimerización supramolecular impulsada por el enlace de hidrógeno de amida autocomplementario.
- Identificación de una interacción n → π* que involucre el átomo de azufre puente.
- La oxidación a la sulfona aumenta la interacción n → π*, lo que lleva a una mayor polimerización y alargamiento.
- La evidencia experimental (constantes de alargamiento, frecuencias vibratorias, cristalografía) apoya el papel de los efectos estereoelectrónicos.
Conclusiones:
- Los 2,11-dithia[3.3]paraciclophanes pueden someterse a la polimerización supramolecular a través del enlace de hidrógeno de amida.
- La interacción n → π* es crucial para el ensamblaje y puede ser modulada por oxidación de azufre.
- Los efectos estereoelectrónicos influyen significativamente en la eficiencia y el alcance de la formación de polímeros supramoleculares.
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