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Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Activación de los enlaces C-H de los arenos: selectividad y reactividad en los complejos bis (pyridyl) platino (II)
Fenbao Zhang1, Christopher W Kirby, Douglas W Hairsine
1Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7.
Journal of the American Chemical Society
|October 13, 2005
Resumen
Los complejos de platino catalizan la activación del enlace C-H del areno. El ligando bis ((pyridyl) influye en los resultados de la reacción, con los sustituyentes metilo y methoxy dirigiendo la selectividad de manera diferente.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Química sintética de la química sintética.
Sus antecedentes:
- Los complejos de platino son valiosos catalizadores en la síntesis orgánica.
- Comprender los efectos de los ligandos es crucial para controlar la reactividad y la selectividad en las reacciones de activación C-H.
Objetivo del estudio:
- Para investigar la influencia de un ligando bis ((pyridyl) en la activación del enlace C-H del areno catalizado por platino.
- Explorar el efecto de los sustituyentes de areno en la regioselectividad de la metalización.
Principales métodos:
- Reacción de un complejo de dimetilo platino con B(C6F5) 3 / H2O en el trifluoroetanol.
- Uso de arenos (Ar-H) con varios sustituyentes (metilo, metoxí) como sustratos.
- Análisis de la formación de productos basado en la quelación de ligandos y efectos de sustitución.
Principales resultados:
- La formación del producto platino-areno [PtAr{HOB{(C6F5)3}{LL) ] depende del tamaño del anillo de quelato formado por el ligando bis{(piridil) (seis miembros favorecidos sobre los cinco miembros).
- Las arenas sustituidas por metilo exhiben una meta > para > orto selectividad para la metalización.
- Las arenas sustituidas por metoxí muestran una orto > meta, para selectividad para la metalización.
Conclusiones:
- El modo de quelación del ligando bis ((pyridyl) dicta la viabilidad de la funcionalización C-H del areno catalizado por platino.
- La identidad del sustituto en la arena juega un papel crítico en la determinación de la regioselectividad de la metalización C-H, con factores electrónicos y estéricos que probablemente gobiernan las preferencias observadas.
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