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Ensamblaje disipador de anhídridos acuosos de ácido carboxílico alimentados por carbodiimidas
Lasith S Kariyawasam1, C Scott Hartley1
1Department of Chemistry & Biochemistry, Miami University , Oxford, Ohio 45056, United States.
Journal of the American Chemical Society
|August 5, 2017
Resumen
Los químicos crearon enlaces covalentes transitorios utilizando carbodiimidas como combustibles para el autoensamblaje. Este trabajo permite la química de nuevos sistemas abióticos, formando macrociclos que responden a los huéspedes cationales.
Área de la Ciencia:
- Química
- Ciencias de los materiales
- Química supramolecular
Sus antecedentes:
- Los sistemas bioquímicos utilizan comúnmente combustibles químicos como el ATP, pero los sistemas abióticos análogos son raros.
- Los enlaces covalentes transitorios son cruciales para la química y el autoensamblaje de los sistemas de no equilibrio.
- El desarrollo de transformaciones adaptables utilizando combustibles fácilmente disponibles es un desafío clave.
Objetivo del estudio:
- Identificar combustibles químicos simples para el ensamblaje disipatorio en sistemas abióticos.
- Demostrar el uso de carbodiimidas para generar enlaces covalentes transitorios.
- Para crear anfitriones supramoleculares fuera de equilibrio.
Principales métodos:
- Se utilizan carbodiimidas, específicamente 1-etil-3-(3-(dimetilamino) propil) carbodiimida (EDC), para formar anhídridos a partir de ácidos carboxílicos en el agua.
- Se ha investigado la formación de anhídridos intramoleculares de diacidos de oligo (etilenglicol) para producir macrociclos.
- Analizó la cinética y los rendimientos de la formación del macrociclo en respuesta a los invitados catiónicos.
Principales resultados:
- Se han generado con éxito anhídridos alifáticos y aromáticos utilizando EDC como combustible, sin incorporar el combustible a las especies transitorias.
- Macrociclos sintetizados análogos a éteres de la corona a través de la formación de anhídridos intramoleculares.
- Se observó que los invitados catiónicos influían en la cinética y los rendimientos de la formación del macrociclo, con cationes coincidentes que disminuían la producción.
Conclusiones:
- Las carbodiimidas sirven como combustibles químicos efectivos para el ensamblaje disipatorio, lo que permite la creación de estructuras covalentes transitorias.
- El método desarrollado proporciona una ruta hacia la química de los sistemas de no equilibrio abiótico y la construcción de huéspedes supramoleculares.
- La naturaleza de respuesta catiónica de los macrociclos destaca su potencial en aplicaciones de detección y reconocimiento molecular.
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