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Plasticidad del níquel (II) entorno de coordinación en complejos con ligandos de tioéter fosfino hemilabílico
Charles W Machan1, Alexander M Spokoyny, Matthew R Jones
1Department of Chemistry and the International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
Journal of the American Chemical Society
|February 16, 2011
Resumen
Nuevos complejos de níquel (II) con ligandos de fosfino-tioéter (P,S) muestran un intercambio único de ligandos de cloruro. Estas reacciones implican cambios dinámicos en la geometría, ofreciendo información sobre la química de la coordinación.
Área de la Ciencia:
- Coordinación Química de la Coordinación
- Química organometálica Química orgánica de los metales.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Se sintetizan complejos homoligados de níquel (II) con los ligandos quelatantes del tioéter fosfino (P,S).
- Los análogos existentes d(8) Rh ((I), Pt ((II) y Pd ((II) no exhiben procesos de intercambio in situ similares.
Objetivo del estudio:
- Síntesis y caracterización de nuevos complejos homoligados de Ni (II).
- Investigar los procesos únicos de intercambio de ligandos de cloruro in situ observados en estos complejos de Ni (II).
- Para explorar las transformaciones geométricas mediadas por contraaniones y ligandos hemilabiles.
Principales métodos:
- Síntesis y caracterización de los complejos de Ni (II).
- Experimentos de abstracción e introducción de iones de cloruro in situ.
- Difracción de rayos X de un solo cristal.
- Solución (31) P{(1) H} Espectroscopia de RMN. espectroscopia de RMN.
- Espectroscopia UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis. espectroscopía UV-vis.
- Cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- Los complejos octaédricos de Ni (II) se someten a una disociación reversible del ligando del cloruro.
- Los procesos de intercambio proceden a través de intermediarios piramidal cuadrado, tetraédrico y plano cuadrado.
- Se establecen procedimientos sintéticos para la mediación de transformaciones geométricas utilizando contraaniones y ligandos hemilabiles.
Conclusiones:
- Los complejos sintetizados de Ni (II) muestran un comportamiento dinámico sin precedentes centrado en el intercambio de ligandos de cloruro.
- El estudio proporciona una estrategia sintética general para controlar las transformaciones geométricas en complejos relacionados.
- Estos hallazgos contribuyen a una comprensión más profunda de la reactividad y la diversidad estructural en los complejos metálicos d(8).
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