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Funcionalización estéricamente dirigida de la clase de ligando redox activo bis(imino) acenafteno: una investigación
Daniel A Evans1, Ignacio Vargas-Baca, Alan H Cowley
1Department of Chemistry and Biochemistry, The University of Texas at Austin , Austin, Texas 78712, United States.
Journal of the American Chemical Society
|September 6, 2013
Resumen
El obstáculo estérico dirige la funcionalización de los ligandos redox-activos bis(imino) acenafteno (BIAN). Dependiendo del volumen estérico, las reacciones proceden a través de la dearomatización radical o la alquilación nucleofílica, ofreciendo nuevas rutas sintéticas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Coordinación Química de la Coordinación
- Química computacional es la química computacional.
Sus antecedentes:
- Los ligandos de bis ((imino) acenafteno (BIAN) son redox-activos y estéricamente sintonizables.
- Comprender las vías de funcionalización es crucial para el diseño de ligandos.
Objetivo del estudio:
- Para explorar la funcionalización estéricamente dirigida de los ligandos Ar-BIAN.
- Para aclarar los mecanismos de las vías de funcionalización de Ar-BIAN.
Principales métodos:
- Síntesis y caracterización de los derivados de Ar-BIAN.
- Difracción de rayos X monocristalino para la determinación estructural.
- Espectroscopia de resonancia paramagnética de electrones (EPR) para el monitoreo de reacciones.
- Teoría Funcional de Densidad con Dispersión (DFT-D) cálculos para conocimientos mecanicistas.
Principales resultados:
- La congestión estérica alrededor del fragmento N-C-C-N dicta las vías de funcionalización.
- Se identificaron dos vías distintas: la desaromatización radical de la columna vertebral y la C-alquilación de imina nucleofílica.
- Estructuras de nuevos derivados de Ar-BIAN (14-19) confirmadas por difracción de rayos X.
Conclusiones:
- El control estérico es un factor clave para dirigir la funcionalidad de Ar-BIAN.
- Los cálculos DFT-D explican con éxito las vías de reacción observadas y las fuerzas motrices.
- Este estudio proporciona un marco para el diseño de ligandos BIAN funcionalizados con reactividad predecible.
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