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Una "bisagra de pivote molecular" basada en la conmutación intramolecular regulada por el pH de las interacciones
Chi-Kin Koo1, Benny Lam, Sze-Kar Leung
1Department of Biology & Chemistry, City University of Hong Kong, Tat Chee Avenue, Hong Kong SAR, China.
Journal of the American Chemical Society
|December 21, 2006
Resumen
Este estudio revela un nuevo complejo cicloplatinado binuclear que actúa como una bisagra de pivote molecular. Su apertura y cierre reversibles están controlados por las interacciones Pt-Pt y la protonación del ligando.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química supramolecular de las moléculas.
- Coordinación Química de la Coordinación
Sus antecedentes:
- Los complejos de platino ciclometalizados son de interés por sus propiedades estructurales y fotofísicas únicas.
- Las máquinas y interruptores moleculares son cruciales para el desarrollo de materiales funcionales avanzados.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo cicloplatinado binuclear. complejo.
- Para investigar su potencial como un pivote molecular impulsado por interacciones reversibles.
Principales métodos:
- Síntesis del complejo binuclear {[Pt(L) ]2(mu-dppm)}2+ (1) utilizando un nuevo ligando ciclometalizante HL (2-fenil-6-(1H-pirazol-3-il) piridina).
- Análisis espectroscópicos y estructurales para confirmar la formación y las propiedades del complejo.
- Investigación del comportamiento del complejo bajo diferentes condiciones de pH para estudiar el mecanismo de bisagra.
Principales resultados:
- El complejo {[Pt(L) ]2(mu-dppm)}2+ (1) exhibe un comportamiento molecular de pivote y bisagra.
- El mecanismo de la bisagra incluye interacciones reversibles Pt-Pt d8-d8 y apilamiento pi-pi intramolecular.
- La protonación/deprotonación del grupo pyrazolyl-NH en el ligando L controla la formación y escisión de estas interacciones.
Conclusiones:
- El complejo cicloplatinado binuclear funciona como una bisagra molecular sensible.
- Este sistema demuestra un nuevo mecanismo para controlar el movimiento molecular a través de las interacciones metal-metal y pi-pi.
- Los hallazgos abren caminos para diseñar nuevos sistemas supramoleculares sensibles a los estímulos.
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