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Las porfirinas como catalizadores fotorreductivos: estudios experimentales y teóricos

Katarzyna Rybicka-Jasińska¹, Wenqian Shan², Katarzyna Zawada³

¹Institute of Organic Chemistry, Polish Academy of Sciences , Kasprzaka 44/52, 01-224 Warsaw, Poland.

Journal of the American Chemical Society

|December 10, 2016

Resumen

Las porfirinas de base libre, como H2TPP, son catalizadores fotorredóxicos efectivos para sintetizar derivados alfa-alquilados de aldehídos y compuestos diazo. Modificar la estructura de la porfirina optimiza el rendimiento catalítico.

Área de la Ciencia:

Química orgánica
Fotocatálisis
Catálisis

Sus antecedentes:

Las metaloporfirinas son cruciales en biología y síntesis orgánica.
Las funciones catalíticas de las porfirinas de base libre, más allá de la fotosensibilización, son menos conocidas.
Las porfirinas pueden participar en la transferencia de electrones bajo irradiación.

Objetivo del estudio:

Explorar el potencial catalítico de las porfirinas de base libre en la síntesis orgánica.
Investigar la tetrafenilporfirina de base libre (H2TPP) como catalizador fotorredóxico.
Para demostrar la síntesis de derivados alfa-alquilados utilizando aldehídos y compuestos diazo.

Principales métodos:

Utilizando la tetrafenilporfirina de base libre (H2TPP) como catalizador fotorredóxico.
Empleando una reacción entre aldehídos y compuestos diazo.
Investigar el impacto de los sustituyentes periféricos en las propiedades y la actividad de la porfirina.

Principales resultados:

La tetrafenilporfirina de base libre (H2TPP) demostró su eficacia como catalizador fotorredóxico.
La reacción produjo con éxito derivados alfa-alquilados.
Adaptación de los sustituyentes en el macrociclo de la porfirina, afinando las propiedades ópticas y electroquímicas.

Conclusiones:

Las porfirinas de base libre son catalizadores fotorredóxicos viables para transformaciones orgánicas específicas.
La modificación estructural de las porfirinas permite la optimización de la actividad catalítica.
Este trabajo amplía las aplicaciones conocidas de las porfirinas en catálisis.

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