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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Síntesis de polirotaxanos conjugados orgánicamente solubles por polimerización de rotaxanos enlazados
Jun Terao1, Susumu Tsuda, Yuji Tanaka
1Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, and PRESTO, Japan Science and Technology Agency (JST), Nishikyo-ku, Kyoto 615-8510, Japan. terao@scl.kyoto-u.ac.jp
Journal of the American Chemical Society
|October 17, 2009
Resumen
Los investigadores desarrollaron un nuevo método para crear polirotaxanos basados en ciclodextrina. Estos nuevos cables moleculares aislados ofrecen una mejor solubilidad, relación de cobertura y fotoluminiscencia para aplicaciones avanzadas de polímeros.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- La ciencia de los polímeros es la ciencia de los polímeros.
Sus antecedentes:
- Los anteriores polirotaxanos basados en ciclodextrina para aislar polímeros pi-conjugados tenían limitaciones.
- Estas limitaciones incluyen bajos y inconsistentes ratios de cobertura y mala solubilidad en disolventes orgánicos.
Objetivo del estudio:
- Desarrollar un nuevo método para sintetizar polirotaxanos permetilados basados en ciclodextrina.
- Para crear alambres moleculares aislados con propiedades mejoradas como solubilidad, relación de cobertura, rigidez y eficiencia de fotoluminiscencia.
Principales métodos:
- Síntesis de polirotaxanos permetilados basados en ciclodextrina a través de la polimerización de monómeros de rotaxano enlazados.
- Caracterización de los polirotaxanos resultantes para la solubilidad, la relación de cobertura, la rigidez y la fotoluminiscencia.
Principales resultados:
- El nuevo método produjo polirotaxanos altamente solubles en disolventes orgánicos.
- Se obtienen altas relaciones de cobertura, una mayor rigidez y una mejor eficiencia de la fotoluminiscencia.
- Se observó una fase de cristal líquido colestérico en los polirotaxanos altamente rígidos.
Conclusiones:
- El nuevo método de polimerización supera las limitaciones de los enfoques anteriores.
- Los polirotaxanos resultantes son materiales prometedores para aplicaciones avanzadas que requieren cadenas de polímeros pi-conjugados aislados.
- La fase de cristal líquido observada pone de relieve las propiedades estructurales y físicas únicas de estos nuevos polirotaxanos.
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