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Published on: April 27, 2017
Los complejos de 3H-benzofosfepina: versátiles precursores del fosfinideno.
Mark L G Borst1, Rosa E Bulo, Danièle J Gibney
1Department of Chemistry, Faculty of Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
Journal of the American Chemical Society
|December 1, 2005
Resumen
Los investigadores sintetizaron complejos de benzofosfepina a través de la hidrofosfinación del 1,2-dietilbenceno. Estos complejos actúan como precursores de fosfinideno, siendo la isomerización el paso que determina la velocidad de su formación.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química sintética de la química sintética.
Sus antecedentes:
- Los complejos de benzofosfeína son valiosos intermediarios sintéticos.
- La hidrofosfinación ofrece una ruta a complejos heterociclos que contienen fósforo.
Objetivo del estudio:
- Para detallar la síntesis de los complejos de benzophosphepine.
- Para investigar su utilidad como precursores de fosfinideno.
- Para dilucidar el mecanismo de reacción.
Principales métodos:
- Dos reacciones sucesivas de hidrofosfinación de 1,2-dietinilebenceno.
- El uso de varios complejos metálicos de carbonilo (W, Mo, Cr, Mn).
- Análisis cinético y computacional.
Principales resultados:
- La síntesis exitosa de diversos complejos de benzophosphepine.
- Identificación de las benzeno-1,4-difosfinanas como productos secundarios.
- Demostración de la generación de fosfinideno a temperaturas elevadas (>55°C).
- La isomerización fosfeína-fosfanorcaradieno fue identificada como determinante de la velocidad.
Conclusiones:
- Los complejos de Benzophosphepine se sintetizan fácilmente y sirven como precursores efectivos del phosphinidene.
- La vía de reacción implica un paso clave de isomerización.
- Los fosfinidenos transitorios pueden someterse a reacciones adicionales, formando complejos de difosfireno.
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