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La organización jerárquica de las rosetas fotorresponsivas con enlaces de hidrógeno
Shiki Yagai1, Toshiharu Nakajima, Keiki Kishikawa
1Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan. yagai@faculty.chiba-u.jp
Journal of the American Chemical Society
|August 4, 2005
Resumen
Los investigadores crearon un nuevo organogel fotorresponsivo utilizando supramoleculas en forma de disco. Este gel es un gel.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
Sus antecedentes:
- Los agregados en forma de disco (rosetas) enlazados con hidrógeno se forman a partir de melamina y barbitúricos/cianuratos aplicados con azobenzeno.
- Estas rosetas exhiben una organización jerárquica y un comportamiento fotorresponsivo.
Objetivo del estudio:
- Investigar la organización jerárquica y el comportamiento fotorresponsivo de las rosetas a base de azobenzeno.
- Desarrollar organogeles fotorresponsivos utilizando supramoleculas en forma de disco.
Principales métodos:
- La espectroscopia de resonancia magnética nuclear (RMN) también se conoce como espectroscopia de resonancia magnética nuclear.
- Espectroscopia UV / vis espectroscopía UV / vis.
- La dispersión dinámica de la luz (DLS, por sus siglas en inglés)
- Estudios de la gelación.
- Modelado molecular y modelado molecular.
Principales resultados:
- Las rosetas a base de barbitúricos formaron mesofasas columnares rectangulares a granel, pero no agregados de orden superior en disolventes.
- Las rosetas a base de cianurato formaron mesofasas columnares hexagonales a granel y agregados fibrosos en disolventes, lo que condujo a la formación de organogel.
- La irradiación UV indujo la disociación reversible y la reformación de los agregados columnares a través de la isomerización trans-cis del azobenzeno.
- El modelado molecular mostró que las rosetas de cis-azobenzeno pierden planaridad.
Conclusiones:
- Las rosetas a base de azobenzeno pueden formar mesofasas columnares y organogeles.
- La fracción de azobenzeno permite el autoensamblaje y desensamblaje fotocontrolado.
- Se creó con éxito un nuevo organogel fotorresponsivo utilizando supramoleculas en forma de disco.
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