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Reductive Electropolymerization of a Vinyl-containing Poly-pyridyl Complex on Glassy Carbon and Fluorine-doped Tin Oxide Electrodes
Published on: January 30, 2015
TTF vinilógico cíclico: un clip molecular potencial activado por la transferencia de electrones
Michel Guerro1, Roger Carlier, Kamal Boubekeur
1Synthèse et Electrosynthèse Organiques, UMR CNRS 6510, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France.
Journal of the American Chemical Society
|March 6, 2003
Resumen
Los vinílogos tetratiafulvalenos cíclicos (TTF) experimentan movimientos moleculares significativos después de la oxidación. La longitud de la cadena de alquilo dicta si se produce un movimiento de estiramiento o recorte, ofreciendo un control reversible a bajos potenciales.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Ciencia de los materiales Ciencia de los materiales.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los vinílogos cíclicos tetratiafulvalenos (TTF) son moléculas orgánicas redox activas.
- Las máquinas y actuadores moleculares se basan en movimientos moleculares controlados.
Objetivo del estudio:
- Para sintetizar vinílogos cíclicos tetratiafulvalenos con diferentes longitudes de la cadena de alquilo.
- Investigar las propiedades electroquímicas y los cambios conformacionales de estos derivados de TTF.
- Para correlacionar la estructura molecular con los movimientos observados.
Principales métodos:
- Acoplamiento intramolecular oxidativo de bis ((dithiafulvenes) para la síntesis.
- Análisis electroquímico (voltametría cíclica).
- Cristalografía de rayos X para la determinación estructural.
- Cálculos de geometría molecular.
Principales resultados:
- Síntesis exitosa de TTFs vinílogos cíclicos con longitudes de cadena de alquilo ajustables.
- Observación de movimientos moleculares grandes y reversibles (estiramiento o recorte) tras la oxidación de bajo potencial.
- Correlación entre la longitud de la cadena de alquilo y el tipo de cambio conformacional.
- Influencia insignificante de los sustituyentes o obstáculo estérico en el espaciador central.
Conclusiones:
- Los TTFs vinílogos cíclicos sirven como actuadores moleculares eficientes.
- La longitud de la cadena de alquilo es un parámetro clave para controlar el movimiento molecular en estos sistemas.
- Estos sistemas basados en TTF ofrecen cambios de conformación rápidos, reversibles y de bajo potencial.
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