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Pilar[6] complejación anfitrión-invitado fotorresponsivo basado en arenos
Guocan Yu1, Chengyou Han, Zibin Zhang
1Department of Chemistry, Zhejiang University, Hangzhou, People's Republic of China.
Journal of the American Chemical Society
|May 1, 2012
Resumen
Las arenas de pilares fotorresponsivos[6] forman complejos huésped-huésped con huéspedes trans-azobenzeno, lo que permite la agregación controlada por la luz. Este sistema supramolecular ofrece un nuevo motivo con foto conmutable para el reconocimiento molecular.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los derivados de azobenzeno son ampliamente utilizados en la química huésped-huésped para aplicaciones fotorresponsivas.
- Las arenas pilares, anfitriones macrocíclicos, exhiben la unión selectiva de huéspedes por tamaño en función de las dimensiones de sus cavidades.
- Los sistemas huésped-invitado existentes, como la ciclodextrina/azobenzeno, están bien establecidos, pero tienen limitaciones.
Objetivo del estudio:
- Para investigar la complejación huésped-huésped de los derivados de azobenzeno con pilares[6]arenos.
- Para explorar el comportamiento fotorresponsivo de los complejos pillarareno-azobenzeno.
- Desarrollar un nuevo sistema supramolecular con foto conmutable para el reconocimiento molecular en disolventes orgánicos.
Principales métodos:
- Síntesis y caracterización del areno pilar[6] y de los anfitriones del areno pilar[5].
- Estudios de complejación huésped-huésped utilizando huéspedes que contienen azobenzeno.
- Estudios de agregación fotocontrolados utilizando radiación UV y luz visible.
Principales resultados:
- El areno pilar[6] forma selectivamente complejos anfitrión-invitado con el isómero trans del azobenzeno, a diferencia de los arenos pilar[5], debido a las diferencias de tamaño de la cavidad.
- La complejación anfitrión-invitado entre el pilar[6]areno y el azobenzeno se somete a una agregación fotoinducida reversible.
- La irradiación con rayos UV y luz visible cambia el estado de agregación entre estructuras irregulares y vesiculares.
Conclusiones:
- El pilar[6]arene sirve como un huésped fotorresponsivo para los huéspedes de azobenzeno, lo que demuestra un reconocimiento selectivo por tamaño.
- El sistema desarrollado exhibe agregación fotocontrolada reversible, ofreciendo un nuevo motivo de foto conmutable.
- Este sistema basado en pilarareno es eficaz en disolventes orgánicos y complementa los motivos de reconocimiento existentes.
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