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Inversión de cara fotoinducida de los ligandos de tetraeno conjugados en una fracción Pd-Pd-Pd

Tetsuro Murahashi¹, Yutaka Higuchi, Tetsuya Katoh

¹Department of Applied Chemistry and Frontier Research Center, Faculty of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan. tetsu@chem.eng-u.ac.jp

Journal of the American Chemical Society

|November 28, 2002

Resumen

Se observó la isomerización fotoinducida de complejos de tripalladio en sándwich lineal. La luz visible causó un cambio entre los arreglos escalonados (rac) y eclipsados (meso) de los ligandos de tetraeno, confirmado por cristalografía de rayos X.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La fotoquímica es la fotoquímica.
La cristalografía es una técnica de cristalografía.

Sus antecedentes:

Los complejos de tripalladio de sándwich lineal exhiben propiedades estructurales únicas.
Los ligandos de tetraeno en estos complejos pueden sufrir cambios conformacionales.

Objetivo del estudio:

Para investigar la isomerización fotoinducida de complejos de tripalladio en sándwich lineal.
Para dilucidar las transformaciones estructurales que involucran ligandos tetraeno tras la irradiación.

Principales métodos:

Irradiación de complejos de tripalladio con luz visible (>510 nm).
Determinación estructural de isómeros mediante análisis cristalográficos de rayos X.

Principales resultados:

Se logró la isomerización fotoinducida de las formas rac (sandwich escalonado) a meso (sandwich eclipsado).
Se determinaron con éxito las estructuras de los isómeros rac y meso.

Conclusiones:

La luz visible desencadena una isomerización de inversión de cara en complejos de tripalladio en sándwich lineal.
La cristalografía de rayos X proporciona evidencia estructural definitiva para la transformación rac-meso observada.

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