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Diferencias dramáticas en la emisión inducida por la agregación y la polimerizabilidad supramolecular de

Hui-Qing Peng^1,2, Xiaoyan Zheng¹, Ting Han^1,2

¹Department of Chemistry, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Institute of Molecular Functional Materials, Institute for Advanced Study, State Key Laboratory of Neuroscience, Division of Biomedical Engineering and Division of Life Science, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong 999077, China.

Journal of the American Chemical Society

|July 11, 2017

Resumen

Los investigadores sintetizaron isómeros geométricos distintos de tetrafeniletenos funcionalizados con ureidopirimidina ((Z) -TPE-UPy y (E) -TPE-UPy). Estos isómeros exhiben propiedades fluorescentes únicas y aplicaciones potenciales en detección y fabricación de materiales.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
Química supramolecular

Sus antecedentes:

Los isómeros geométricos (Z) y (E) son cruciales en la vida y la ciencia de los materiales, sin embargo, su separación y confirmación estructural plantean desafíos.
La ingeniería molecular se basa en el diseño de nuevos isómeros con diversas propiedades y funcionalidades.
Los derivados del tetrafenileteno (TPE) son conocidos por su emisión inducida por agregación (AIE), mientras que la ureidopirimidina (UPy) permite la polimerización supramolecular.

Objetivo del estudio:

Sintetizar y caracterizar los isómeros geométricos puros de los tetrafeniletenos funcionalizados con ureidopirimidina ((Z) -TPE-UPy y (E) -TPE-UPy).
Investigar las distintas propiedades fotofísicas y las aplicaciones potenciales de estos isómeros.
Aprovechar la AIE combinada del TPE y la polimerizabilidad supramolecular del UPy para materiales avanzados.

Principales métodos:

Síntesis exitosa de isómeros puros de (Z) -TPE-UPy y (E) -TPE-UPy.
Confirmación de la estructura mediante las espectroscopias de resonancia magnética nuclear (RMN) 2D COSY y NOESY.
Caracterización de las propiedades de fluorescencia en el estado agregado.

Principales resultados:

Fluorescencia de estado agregado distinto: (Z) -TPE-UPy muestra emisión verde, mientras que (E) -TPE-UPy emite luz azul.
La cavidad en (Z) -TPE-UPy facilita su uso en la detección de iones de mercurio (Hg2+).
Los polímeros de alto peso molecular de (E) -TPE-UPy se pueden fabricar en fibras fluorescentes y fotopatrones.

Conclusiones:

El estudio sintetizó y caracterizó con éxito distintos isómeros geométricos de TPE-UPy, demostrando sus propiedades únicas.
Estos isómeros ofrecen fluorescencia ajustable y potencial para aplicaciones avanzadas en sensores químicos y materiales optoelectrónicos.
Los hallazgos contribuyen al desarrollo de nuevos materiales funcionales a través de un diseño molecular preciso y control de isómeros.

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