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Borilación de azaciclos catalizada por iridio enantioselectiva α-C ((sp^{3)) -H}

Lili Chen¹, Yuhuan Yang^1,2, Luhua Liu^1,2

¹State Key Laboratory for Oxo Synthesis and Selective Oxidation, Center for Excellence in Molecular Synthesis, Suzhou Research Institute, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People's Republic of China.

Journal of the American Chemical Society

|June 30, 2020

Resumen

Este estudio introduce un método catalizado por iridio para la borilación C-H enantioselectiva de azaciclos. El nuevo enfoque permite la síntesis de azaciclos quirales valiosos con alta selectividad a partir de precursores simples.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los azaciclos son compuestos heterocíclicos importantes en la química medicinal.
Los métodos eficientes para la funcionalización enantioselectiva de los azaciclos son muy buscados.
La activación y la borilación de C-H ofrecen rutas directas a las moléculas funcionales.

Objetivo del estudio:

Desarrollar una nueva borilación enantioselectiva α-C ((sp3) -H catalizada por iridio de azaciclos.
Explorar el alcance y las limitaciones de esta nueva metodología sintética.
Proporcionar acceso a los derivados de azaciclo enriquecidos enantioméricamente.

Principales métodos:

Utilizó un precursor de iridio en combinación con un ligando de borilo bidentado quiral.
Investigó la borilación enantioselectiva α-C ((sp3) -H de varios azaciclos.
Condiciones de reacción optimizadas para lograr una alta enantioselectividad.

Principales resultados:

Se logró con éxito la borilación enantioselectiva α-C ((sp3) -H de una amplia gama de azaciclos.
Se ha demostrado la capacidad de diferenciar enlaces enantiotrópicos de metileno C-H.
Se obtienen diversos azaciclos sintéticamente útiles con enantioselectividades de buenas a excelentes.
Se utilizan materiales de partida fácilmente disponibles.

Conclusiones:

El método desarrollado catalizado por iridio es eficaz para la borilación C-H enantioselectiva de azaciclos.
Esta metodología proporciona una herramienta valiosa para la síntesis de azaciclos quirales.
El enfoque ofrece una ruta directa y eficiente a los compuestos heterocíclicos enriquecidos enantioméricamente.

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