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Complejos de pinzas de 2-Indenilideno de zirconio y paladio

Pascal Oulié¹, Noel Nebra, Nathalie Saffon

¹Université de Toulouse, UPS, Laboratoire Hétérochimie Fondamentale et Appliquée, 118 route de Narbonne, F-31062 Toulouse, France.

Journal of the American Chemical Society

|February 24, 2009

Resumen

Se sintetizaron nuevos complejos indenil con fosfazeno y los ligandos tiofosfinoil. Estos ligandos apoyan la coordinación del 2-indenilideno con metales como el zirconio y el paladio, principalmente a través de interacciones sigma.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Coordinación Química de la Coordinación
Síntesis Inorgánica y Síntesis Inorgánica.

Sus antecedentes:

Los ligandos de indenilo son versátiles en la química organometálica, ofreciendo modos de coordinación únicos.
Las fracciones de fosfazeno y tiofosfinoil presentan interesantes propiedades electrónicas y estéricas para el diseño de ligandos.

Objetivo del estudio:

Para sintetizar y caracterizar nuevos complejos de indenilo con fosfazeno y thiophosphinoyl brazos laterales.
Para investigar el comportamiento de coordinación de estos ligandos con los centros metálicos de zirconio y paladio.
Para dilucidar las interacciones electrónicas dentro del marco metal-ligando.

Principales métodos:

Síntesis de los derivados del indenilo [IndH{2}{2}{3}{4}P=X}{2}] (X = NMes, S).
Reacciones con los precursores de los metales: tetracis (((dimetilamido)) zirconio y paladio ((II) dicloruro de ciclooctadieno.
Caracterización utilizando espectroscopia de RMN, difracción de rayos X y cálculos de la Teoría Funcional de la Densidad (DFT).

Principales resultados:

Síntesis exitosa de complejos de zirconio {[Ind(Ph(2) PNMes) ((2)) ]Zr(NMe(2)) ((2)) y {[Ind(Ph(2) PS) ((2)) ]Zr(NMe(2)) ((2)).
Formación de un complejo de paladio {[Ind(Ph(2) PS)(2)]Pd(HNc-Hex(2))}.
La evidencia de la coordinación del 2-indenilideno apoyada por los grupos fosfazeno y tiofosfinoilo.
El análisis de DFT reveló interacciones sigma dominantes e interacciones pi insignificantes entre el carbono indenil C2 y el metal.

Conclusiones:

Los brazos laterales de fosfazeno y tiofosfinoilo estabilizan efectivamente el modo de coordinación del 2-indenilideno.
El enlace se caracteriza por una fuerte donación sigma del ligando indenilo al centro metálico.
Estos hallazgos contribuyen a la comprensión de los principios de diseño de ligandos para estabilizar geometrías de coordinación inusuales en complejos organometálicos.

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