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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
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Isomerización fotoinducida de [N2]2- en un complejo de lutecio bimetálico
Mingbin Yuan1, Andrew J McNeece2, Ekaterina A Dolgopolova3
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
Journal of the American Chemical Society
|November 1, 2024
Resumen
Se desarrolló el primer fotointerruptor de lantánido dinitrógeno, que permite la isomerización controlada entre los modos de coordinación lateral y terminal utilizando luz infrarroja cercana. Este descubrimiento abre nuevas vías para las reacciones redox con moléculas orgánicas.
Área de la Ciencia:
- Química inorgánica
- Química organometálica
- La fotoquímica
Sus antecedentes:
- El dinitrógeno (N2) es una molécula estable, y su activación es crucial para la fijación del nitrógeno.
- Los complejos de lantánidos ofrecen propiedades electrónicas únicas para las transformaciones químicas.
- Los modos de coordinación fotointercambiables de los ligandos N2 son en gran parte inexplorados.
Objetivo del estudio:
- Para reportar el primer fotointerruptor de lantánido dinitrógeno.
- Investigar la isomerización controlada entre los modos de coordinación lateral y terminal de un ligando de nitrógeno.
- Para explorar las propiedades fotocrómicas y la reactividad de estos complejos.
Principales métodos:
- Síntesis y caracterización de complejos de nitrógeno de lutecio bimetálico.
- La fotoisomerización inducida por la luz del infrarrojo cercano (NIR).
- Difracción única de rayos X (XRD) y espectroscopia de Raman para el análisis estructural.
- Cálculos de los primeros principios para estudios de estructura electrónica y mecanicistas.
Principales resultados:
- Se sintetizó el primer fotointerruptor de lantánido dinitrógeno, C5Me4H2THFLu2μ-η2:η2-N2 (1).
- La isomerización reversible inducida por la luz infrarroja al isómero final, [{C5Me4H}2{THF}Lu]2{μ-η1:η1-N2} (2).
- La configuración original de ligando y disolvente fue esencial para el fotocromismo.
- Se aclararon los detalles mecánicos y las estructuras electrónicas de la isomerización.
- El complejo 2 reaccionó con antraceno, produciendo dimeros de dihidroantraceno y antraceno.
Conclusiones:
- Se ha descubierto un nuevo fotointerruptor de lantánido dinitrógeno que exhibe fotocromatismo.
- La isomerización de lado a extremo se puede controlar a través de la luz NIR.
- El fotointerruptor demuestra el potencial de nuevas vías de reacción redox.
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