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Adición de radicales intermoleculares a los cetoácidos habilitados por la activación del boro

Shasha Xie¹, Defang Li^1,2, Hanchu Huang¹

¹State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road , Shanghai 200032 , China.

Journal of the American Chemical Society

|October 2, 2019

Resumen

Los investigadores desarrollaron un nuevo método para la adición radical a los carbonilos utilizando luz visible y activación de boro. Este enfoque sintetiza eficientemente diversos lactatos y precursores farmacéuticos en condiciones suaves y libres de metales.

Área de la Ciencia:

Química orgánica
Química sintética
La fotoquímica

Sus antecedentes:

La adición de radicales intermoleculares a los carbonilos es un desafío debido a la fragmentación de los radicales alcoxilo.
La construcción de centros de carbono cuaternarios a través de la adición radical a las cetonas sigue siendo un obstáculo sintético.

Objetivo del estudio:

Desarrollar un nuevo método inducido por luz visible para la adición de radicales intermoleculares a los α-cetoácidos.
Para permitir la síntesis de diversos lactatos y precursores farmacéuticos.

Principales métodos:

La catálisis de fotorreducción de luz visible combinada con la activación del ácido de Lewis.
Utilizando ácidos alquilo borónicos como precursores de radicales.
Formación de complejos de boro in situ para estabilizar los intermedios.

Principales resultados:

Adición exitosa de ácido alquilo borónico intermolecular a los α-cetoácidos bajo luz visible.
Síntesis de lactatos diversamente sustituidos a temperatura ambiente.
Escalabilidad demostrada de la síntesis de precursores farmacéuticos en condiciones de flujo libre de metales.

Conclusiones:

La estrategia de activación de boro supera los desafíos en la adición radical a los carbonilos.
Este método proporciona una ruta suave, eficiente y escalable a compuestos orgánicos valiosos.
El enfoque es versátil, aplicable a varios precursores de radicales alquilo.

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