La nueva superestructura de los mesógenos nondiscoides: asociación desigual-paralela de las moléculas de medio disco, 3,4,5-trialcoxybenzoic anhidrides, a una estructura columnar y su interdigitación unidireccionalmente orientada
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Stable DNA Motifs, 1D and 2D Nanostructures Constructed from Small Circular DNA Molecules
Published on: April 12, 2019
Keiki Kishikawa1, Shigetaka Furusawa, Takahiro Yamaki
1Department of Materials Technology, Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
Journal of the American Chemical Society
|February 21, 2002
Resumen
Los nuevos anhídridos de ácido cristalino líquido líquido forman fases columnares únicas. Estas moléculas se autoensamblan a través de interacciones dipolo-dipolo, creando columnas interdigitadas unidireccionalmente con estructuras helicoidales potenciales.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
- La cristalografía es una técnica de cristalografía.
Sus antecedentes:
- Los mesógenos nondiscoides son cruciales para el desarrollo de nuevas fases de cristales líquidos.
- Los anhídridos ácidos no han sido explorados previamente como compuestos cristalinos líquidos.
- Comprender el autoensamblaje molecular es clave para diseñar materiales avanzados.
Objetivo del estudio:
- Para diseñar y sintetizar un nuevo ensayo de anhídridos coxybenzoicos.
- Investigar el autoensamblaje y la superestructura de estos compuestos en fases de cristal líquido.
- Para explorar el potencial de la fracción -CO-O-CO- como unión polar.
Principales métodos:
- Síntesis de anhídridos tricoxibenzoicos (compuestos 2-11).
- Caracterización mediante microscopía de luz polarizada, calorimetría de barrido diferencial, cálculos MM2/AM1, espectroscopia de dicroísmo circular y difracción de rayos X.
- Análisis del empaque molecular y el comportamiento de fase.
Principales resultados:
- Los compuestos 5-9 y 11 se autoensamblaron en columnas a través de interacciones dipolo-dipolo de grupos carbonílicos.
- Se observó una nueva fase columnar interdigitada unidireccionalmente, con moléculas dispuestas antiparalelas dentro de columnas.
- Se sugirió una organización helicoidal para el compuesto 11 con cadenas laterales quirales, evidenciada por espectros de dicroísmo circular.
Conclusiones:
- Los anhídridos trialcoxibenzoicos representan la primera clase de anhídridos de ácido cristalino líquido.
- La porción -CO-O-CO- actúa efectivamente como una unión polar para el autoensamblaje en estructuras columnares.
- El estudio demuestra un nuevo método para crear fases de cristales líquidos columnares interdigitados unidireccionalmente.
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