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Efectos electrónicos y estructurales de la borilación y cuaternarización escalonadas en la aromaticidad del borireno
Holger Braunschweig1, Alexander Damme, Rian D Dewhurst
1Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany. h.braunschweig@uni-wuerzburg
Journal of the American Chemical Society
|January 12, 2013
Resumen
Los nuevos borilborirenos fueron sintetizados a través de la fotólisis a temperatura ambiente de un complejo de aminoborilo y alquinas. Estos nuevos compuestos fueron aislados, caracterizados y estudiados por su reactividad con las bases de Lewis.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química del boro y su química.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los complejos de aminoborilo son precursores versátiles en la síntesis inorgánica.
- La funcionalización de las alquinas sigue siendo un área clave en la química sintética.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos compuestos de borilborireno.
- Para investigar la reactividad de estos nuevos compuestos con bases de Lewis.
- Para explorar la estructura electrónica y los efectos de sustitución en los borilborirenos.
Principales métodos:
- Fotólisis a temperatura ambiente de un complejo de aminoborilo y cromo con varios alquinas.
- Aislamiento y caracterización mediante RMN, IR, espectroscopia UV/vis multinuclear, cristalografía y análisis elemental.
- Cálculos de la Teoría Funcional de Densidad (DFT) para estudiar la estructura electrónica.
Principales resultados:
- Aislamiento de tres borilborirenos nuevos: [{RCCR}{μ-BN}{SiMe}{3)}{2)} (7, R = B{NMe}{2)), R' = Ph; 8, R = R' = B{NMe}{2)) {2); 9, R = B{NMe}{2)), R' = SiMe{3) }{2), R' = B{NMe}{3}{4}, R' = B{NMe}{3}{4}, R' = B{NMe}{3}{4}, R' = B{NMe}{4}, R' = B{NMe}{4}, R' = B{NMe}{5}, R' = B{NMe}{4}, R' = B{NMe}{4}, R' = B{NMe}{5}, R' = B{NMe}{6}, R' = B{NMe}{7}, R' = B{NMe}{5} y R' = B{NMe}{6}
- Datos espectroscópicos y cristalográficos detallados confirmaron las estructuras.
- Los estudios de reactividad revelaron interacciones con bases de Lewis, con comparaciones con los borirenos conocidos.
Conclusiones:
- El estudio sintetizó y caracterizó con éxito estructuras de borilborireno sin precedentes.
- Se aclaró la reactividad de estos nuevos compuestos hacia las bases de Lewis.
- Los cálculos de DFT proporcionaron información sobre sus propiedades electrónicas y la influencia de los grupos exocíclicos.
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