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Desaromatización enantioselectiva de los indoles a través del acoplamiento reductivo intermolecular mediado por SmI2

Wen-Yun Zhang¹, Hu-Chong Wang¹, Ye Wang¹

¹State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.

Journal of the American Chemical Society

|May 1, 2023

Resumen

Este estudio introduce un método enantioselectivo para la síntesis de indolinas utilizando dióxido de samario (SmI2) y ligandos quirales. El nuevo enfoque logra altos rendimientos y estereoselectividad en la formación de enlaces carbono-carbono a través del acoplamiento reductor.

Área de la Ciencia:

Química orgánica
Química sintética
Catálisis

Sus antecedentes:

El dióxido de samario (SmI2) es un potente reactivo para las reacciones de acoplamiento reductivo.
La síntesis asimétrica a través de reacciones mediadas por SmI2 es un desafío debido a los radicales intermedios.
El desarrollo de métodos enantioselectivos para la formación de enlaces C-C es crucial en la síntesis orgánica.

Objetivo del estudio:

Informar sobre una desaromatización enantioselectiva de los indolos mediante el acoplamiento reductor intermolecular mediado por SmI2.
Desarrollar una síntesis fácil de moléculas de indolina con dos centros estereogénicos contiguos.
Investigar el mecanismo de este nuevo acoplamiento reductor asimétrico.

Principales métodos:

Utilizando el dióxido de samario (SmI2) como reductor.
Utilizando ligandos quirales de tridentato aminodiol para apoyar el reductor de samario.
Realización de acoplamiento reductivo intermolecular entre indolos y cetonas.
Combinando investigaciones experimentales y computacionales.

Principales resultados:

Se logra una síntesis fácil de moléculas de indolina con un alto rendimiento (hasta el 99%).
Se ha demostrado una alta estereoselectividad (hasta 99:1 er y > 20:1 dr).
Propuso un mecanismo único que involucra la transferencia paralela de un solo electrón y la recombinación radical-radical enantioselectiva.

Conclusiones:

El método desarrollado proporciona una vía eficiente para las indolinas enriquecidas enantioméricamente.
El sistema reductor de samario quiral permite la desaromatización asimétrica de los indoles.
Los hallazgos ofrecen nuevos conocimientos sobre los mecanismos de acoplamiento reductivo mediados por SmI2.

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