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Diarylstannylene activación del hidrógeno o el amoníaco con la eliminación del areno
Yang Peng1, Bobby D Ellis, Xinping Wang
1Department of Chemistry, University of California Davis, One Shields Avenue, Davis, California 95616, USA.
Journal of the American Chemical Society
|August 22, 2008
Resumen
El voluminoso estanileno SnAr'2 reacciona fácilmente con H2, D2 o NH3, formando nuevos compuestos. Los estanilenos menos esterificados permanecieron sin reaccionar bajo las mismas condiciones suaves, destacando el impacto de la masa estérica en la reactividad.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Grupo Principal Química.
- Química del silicio y del estaño Química del silicio y del estaño
Sus antecedentes:
- Los estanylenos son compuestos organotínicos divalentes con una reactividad única.
- El obstáculo estérico juega un papel crucial en la estabilidad y las reacciones de los compuestos del grupo principal de baja coordinación.
Objetivo del estudio:
- Para investigar la reactividad de esteriónicamente exigente stannylenes con moléculas pequeñas.
- Para comprender la influencia de la masa estérica en las vías de reacción de los estanilenos.
Principales métodos:
- Reacción de los estanilenos (SnAr'2, SnAr2#, Sn{N(SiMe3)2}2) con el H2, el D2 y el NH3.
- Análisis de productos de reacción y materiales de partida no reaccionados.
- Correlación de la reactividad con las propiedades electrónicas (separación de energía n-p).
Principales resultados:
- El estericamente impedido stanileno SnAr'2 reaccionó con H2, D2 y NH3 para formar dímeros puenteados: {Ar'Sn(mu-H)}2, {Ar'Sn(mu-D)}2, y {Ar'Sn(mu-NH2)}2, respectivamente.
- Los estanilenos menos agrupados (SnAr2# y Sn{N(SiMe3) 2}2) no mostraron ninguna reacción en condiciones idénticas.
- Las diferencias de reactividad se atribuyeron a las variaciones en la separación de energía n-p y el carácter diradical singular.
Conclusiones:
- El obstáculo estérico afecta significativamente la reactividad de los estanylenos, con sustitutos voluminosos que mejoran la reactividad hacia las moléculas pequeñas.
- La menor separación de energía n-p en SnAr'2 se correlaciona con un mayor carácter diradical singular y una mayor reactividad.
- Este estudio proporciona información sobre las relaciones estructura-reactividad de los compuestos organotínicos.
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