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Las alcoxiaminas sensibles a la luz como precursores versátiles de radicales alquilo y nitróxidos controlados
Marc Baron1, Jason C Morris1, Siham Telitel2,3
1Aix Marseille Univ. , CNRS, Institut de Chimie Radicalaire UMR 7273 , Marseille 13397 , France.
Journal of the American Chemical Society
|February 13, 2018
Resumen
Las alkoxiaminas fotosensibles con cromóforos ofrecen una estrategia de fotoprotección para los nitróxidos, lo que permite una síntesis orgánica controlada. Este método permite una disociación rápida y casi cuantitativa bajo luz UV / visible para aplicaciones como el patrón de superficie.
Área de la Ciencia:
- Química orgánica
- La fotoquímica
- Ciencia de los Polímeros
Sus antecedentes:
- La irradiación UV/luz visible ofrece un control preciso para iniciar las síntesis orgánicas.
- Las funcionalidades del óxido nitroso son sensibles a la degradación a través de procesos redox.
- Las alkoxiaminas pueden diseñarse para proteger grupos funcionales sensibles.
Objetivo del estudio:
- Demostrar las alkoxiaminas con cromóforos como grupos fotoprotectores para los nitróxidos.
- Investigar la disociación de las alcoxiaminas fotosensibles bajo la luz UV/visible.
- Para mostrar la aplicación de esta fotoquímica en la modificación de la superficie.
Principales métodos:
- Estudió la disociación de varias alkoxiaminas fotosensibles.
- Se utiliza la irradiación UV/luz visible a temperaturas comprendidas entre 223 y 298 K.
- Utilizó una alkoxiamina a base de pireno para el acoplamiento de la cadena de polímero en obleas de silicio.
Principales resultados:
- Se observó una rápida (típicamente < 1 hora) y casi cuantitativa disociación de las alkoxiaminas.
- Las tasas de disociación y la eficiencia dependían de la naturaleza del cromóforo.
- Se han producido con éxito superficies con micro patrones mediante el acoplamiento de cadenas de polímero controladas espacialmente.
Conclusiones:
- Las alkoxiaminas con cromóforos protegen eficazmente las funcionalidades del nitróxido de la degradación.
- Las alkoxiaminas fotosensibles proporcionan una herramienta versátil para la síntesis orgánica controlada y la funcionalización de la superficie.
- Esta estrategia de fotoprotección permite un control espacial preciso en las aplicaciones de la ciencia de los materiales.
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