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Bis ((allyl) zinc revisado: enlace sigma versus enlace pi de la coordinación de alelo
Crispin Lichtenberg1, Julien Engel, Thomas P Spaniol
1Institute of Inorganic Chemistry, RWTH Aachen, Landoltweg 1, 52056 Aachen, Germany.
Journal of the American Chemical Society
|May 18, 2012
Resumen
Este estudio revela nuevos modos de coordinación para los compuestos de zinc-alilo, desafiando las visiones tradicionales de las interacciones zinc-alilo. El análisis computacional sugiere que el modo clásico de enlace de alelo es desfavorable para el zinc.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química del estado sólido.
- Química computacional es la química computacional.
Sus antecedentes:
- La química de enlace y coordinación de los ligandos aliloides con el zinc no se entiende completamente.
- Las interpretaciones convencionales de las interacciones zinc-alilo pueden requerir una revisión basada en nuevos datos estructurales.
Objetivo del estudio:
- Para reinvestigar las estructuras en estado sólido de bis ((allyl) zinc y 2-metalil cloro zinc.
- Para dilucidar nuevos modos de coordinación del ligando de alilo en complejos de zinc.
- Evaluar computacionalmente los modos de enlace favorecidos de los ligandos de alilo con zinc.
Principales métodos:
- Cristalografía de rayos X para determinar las estructuras de estado sólido.
- Cálculos de la Teoría Funcional de Densidad (DFT) para investigar las estructuras electrónicas y las preferencias de enlace.
- Análisis de las interacciones zinc-alilo y zinc-olefina.
Principales resultados:
- Descubrimiento de los modos de coordinación cis- y trans-μ(2)-η(1):η(1) para el ligando de alilo en bis(alil) zinc y 2-metalil cloro zinc.
- Los resultados computacionales indican que el modo de enlace η(3) es desfavorable para los ligandos de alelo en los compuestos de zinc.
- Identificación de una interacción rara de zinc-olefina en el producto de monoinserción de bis (allil) zinc con la benzofenona.
Conclusiones:
- El estudio requiere una modificación de la comprensión convencional de las interacciones zinc-alilo.
- Nuevos modos de coordinación resaltan la versatilidad de los ligandos de alilo con zinc.
- Los hallazgos computacionales apoyan escenarios de enlace alternativos sobre el modo clásico η(3) para los sistemas de zinc-alilo.
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