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Regioselectiva bis-funcionalización del dimetallofullereno endodérmico, La2@C80: la distancia La-La extrema
Midori O Ishitsuka1, Shogo Sano, Haruka Enoki
1TARA Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.
Journal of the American Chemical Society
|April 19, 2011
Resumen
La bis-funcionalización de los fullerenos llenos de lantano La(2)@C(80) utilizando adición de carbenos alargó la distancia entre el lantano y el metal. Este estudio detalla los cambios estructurales y electrónicos en estos nuevos derivados de metallofullereno.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- Ciencia de los nanomateriales Ciencia de los nanomateriales
- Química organometálica Química orgánica de los metales.
Sus antecedentes:
- Los metalofullerenos endohedrales (EMF) exhiben propiedades electrónicas y estructurales únicas.
- Los EMF basados en lantano, como La(2)@C(80), son de interés debido a sus aplicaciones potenciales.
Objetivo del estudio:
- Para investigar la bifuncionalización del La(2)@C(80) metalofullereno endodérrico mediante adición de carbenos.
- Para caracterizar los adductos resultantes y analizar las modificaciones estructurales, en particular la distancia lantano-lantano.
Principales métodos:
- Reacciones de adición de carbenos a La(2)@C(80).
- Caracterización espectroscópica (por ejemplo, RMN, espectrometría de masas).
- Análisis de difracción de rayos X monocristalino.
- Cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- La bifuncionalización exitosa de La(2)@C(80) se logró a través de la adición de carbenos.
- La cristalografía de rayos X reveló que las adiciones de carbenos se produjeron en la unión de 6,6 enlaces de la jaula C ((80), induciendo la escisión del anillo.
- Se descubrió que los átomos de lantano estaban colocados en posición colineal con los espirocarbonos.
- Se observó un alargamiento significativo de la distancia La-La en el bisaducto en comparación con el EMF prístino y otros derivados.
- Los cálculos de DFT confirmaron las posiciones metálicas observadas.
Conclusiones:
- La bifuncionalización del carbeno proporciona una vía para modificar la estructura de La(2)@C(80).
- El proceso de funcionalización conduce a cambios estructurales significativos, incluida la deformación de la jaula y las distancias metal-metal alteradas.
- El estudio demuestra la adaptabilidad de las propiedades de los CEM a través de la funcionalización covalente.
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