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Alilación catalítica de aldehídos utilizando alquenos no activados

Shun Tanabe¹, Harunobu Mitsunuma¹, Motomu Kanai¹

¹Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan.

Journal of the American Chemical Society

|July 2, 2020

Resumen

Este estudio introduce un nuevo sistema catalítico para la alilación directa de aldehídos utilizando alquenos simples. Esta reacción impulsada por la luz visible ofrece un enfoque sostenible para la síntesis orgánica valiosa.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis sostenible

Sus antecedentes:

Los alquenos simples son materias primas abundantes y baratas.
La utilización directa de alquenos inertes en la síntesis orgánica selectiva sigue siendo un desafío.

Objetivo del estudio:

Desarrollar un sistema catalítico para la alilación directa de aldehídos utilizando alquenos como materia prima.
Para permitir reacciones en condiciones de luz visible suave con una amplia tolerancia del grupo funcional.

Principales métodos:

Un sistema de catalizador híbrido ternario que combina catalizadores fotorredóxicos, de transferencia de átomos de hidrógeno y complejos de cromo.
Irradiación de luz visible a temperatura ambiente.
Desarrollo de una variante asimétrica utilizando un catalizador de cromo quiral.

Principales resultados:

Alilación catalítica exitosa de aldehídos con alquenos simples, incluidos los alquenos inferiores.
Se ha demostrado una alta tolerancia del grupo funcional.
Se logró una variante asimétrica de la reacción de alilación.

Conclusiones:

El sistema catalítico desarrollado proporciona un método eficiente y selectivo para la funcionalización de alceno.
Este enfoque expande la utilidad de los alquenos simples en la síntesis orgánica.
La variante asimétrica ofrece una vía para productos enriquecidos enantioméricamente.

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