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Published on: March 20, 2017
Energías de enlace rodio-carbono en Tp'Rh ((CNneopentyl)) ((CH2X) H: cuantificación de los efectos de estabilización
Yunzhe Jiao1, Meagan E Evans, James Morris
1Department of Chemistry, University of Rochester, Rochester, New York 14627, United States.
Journal of the American Chemical Society
|April 25, 2013
Resumen
Los investigadores sintetizaron complejos de metil rodio sustituidos y estudiaron su reactividad. Las energías de enlace Rh-C se correlacionaron con las fuerzas de enlace C-H, revelando patrones predecibles para las reacciones de inserción de olefinas.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Coordinación Química de la Coordinación
- Los complejos de rodio.
Sus antecedentes:
- Los derivados de metilo sustituidos de los complejos de rodio son importantes en la catálisis.
- Comprender los factores que influyen en su reactividad es crucial para desarrollar nuevos métodos sintéticos.
Objetivo del estudio:
- Para sintetizar una serie de derivados metilo sustituidos de Tp'Rh(CNneopentyl)(CH2X) H.
- Para investigar su eliminación reductora y las fortalezas de los enlaces metal-carbono.
- Para correlacionar estas propiedades con las fuerzas de enlace C-H y predecir las preferencias de inserción de olefinas.
Principales métodos:
- Síntesis mediante fotólisis o intercambio de hidrocarburos.
- Caracterización mediante espectroscopia de RMN, análisis elemental y cristalografía de rayos X.
- Determinación de las energías de enlace Rh-C utilizando técnicas cinéticas y cálculos DFT.
Principales resultados:
- Síntesis exitosa de productos individuales para todos los derivados.
- Se observó eliminación reductiva limpia para todos los compuestos.
- Se encontraron dos correlaciones lineales entre las energías de enlace Rh-C y las fuerzas de enlace C-H.
- Los cálculos de DFT coincidieron bien con los resultados experimentales.
Conclusiones:
- La fuerza de los enlaces β-C-H predice las preferencias de los productos de inserción de olefinas.
- Las fortalezas de los enlaces Rh-C en los derivados de Rh-CH2X sustituidos por α muestran una tendencia consistente con los hallazgos experimentales.
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