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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
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Isomerización electrocatalítica Z → E de los azobenzenos
Alexis Goulet-Hanssens1, Manuel Utecht2, Dragos Mutruc1
1Department of Chemistry & IRIS Adlershof, Humboldt-Universität zu Berlin , Brook-Taylor-Strasse 2, 12489 Berlin, Germany.
Journal of the American Chemical Society
|December 21, 2016
Resumen
La reducción electroquímica de los azobenzenos permite la isomerización catalítica del isómero Z al E. Esta vía catalizada por electrones mejora la eficiencia del fotointercambio y permite el control de la composición isomérica.
Área de la Ciencia:
- La fotoquímica
- La electroquímica
- Química orgánica
Sus antecedentes:
- Los azobenzenos son ampliamente utilizados como fotointerruptores debido a su isomerización E/Z reversible.
- El control de la vía de isomerización y la eficiencia es crucial para optimizar su rendimiento.
Objetivo del estudio:
- Para investigar el comportamiento electroquímico de los isómeros de azobenzeno.
- Explorar nuevas vías para la isomerización catalítica de los azobenzos.
Principales métodos:
- Síntesis de varios compuestos de azobenzeno.
- Estudios de reducción electroquímica.
- Análisis de la cinética y los mecanismos de isomerización.
Principales resultados:
- El anión radical del isómero Z-azobenzeno sufre una rápida isomerización al isómero E.
- Esta isomerización procede catalíticamente a través de la transferencia de electrones, lo que permite la reducción subsoiquiométrica para isomerizar toda la mezcla.
- Los agentes de transferencia de fotoelectrones pueden revertir la dirección de isomerización, anulando las vías intrínsecas desencadenadas por la luz.
Conclusiones:
- La reducción electroquímica ofrece un método potente para la isomerización catalítica de los azobenzenos.
- Este enfoque mejora la eficiencia del fotointercambio y proporciona un nuevo control sobre las poblaciones de isómeros.
- Los hallazgos tienen amplias implicaciones para optimizar las aplicaciones de los fotointerruptores basados en el azobenceno.
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