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Policiclización asimétrica catalítica de las enamidas terciarias con éteres de enol de silicio: síntesis total de (-)

Qing-Bo Zhuang¹, Jin-Rui Tian¹, Ka Lu¹

¹State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.

Journal of the American Chemical Society

|November 29, 2023

Resumen

Un nuevo método catalítico permite la síntesis de N-heterociclos complejos con múltiples estereocentros. Este enfoque se demuestra en la síntesis total del producto natural (-) -cefalociclidina A.

Área de la Ciencia:

Química orgánica
Química sintética
Catálisis

Sus antecedentes:

Los N-heterociclos son estructuras centrales en muchos productos naturales.
Hay una gran demanda de métodos eficientes para la construcción de andamios heterocíclicos complejos.
Los centros estereogénicos cuaternarios son difíciles de sintetizar enantioselectivamente.

Objetivo del estudio:

Desarrollar una nueva reacción de policiclización enantioselectiva catalítica.
Crear N-heterociclos ciclicos y tricíclicos con estereocentros aza y oxacuaternarios.
Mostrar la utilidad de este método en la síntesis de productos naturales.

Principales métodos:

En el caso del cobre (II) triflato (Cu (OTf) 2), el proceso de catálisis es el siguiente:
Utilizando un nuevo ligando de oxazol derivado de la espiropirrolina (SPDO).
Reacción en tándem que involucra a las enamidas terciarias y los éteres de sililenoles.

Principales resultados:

Desarrolló una policiclización enantioselectiva de las enamidas terciarias con éteres de sililenoles.
Se han sintetizado con éxito N-heterociclos bicíclicos y tricíclicos que contienen estereocentros cuaternarios.
Se aplicó la metodología a la síntesis total de (-) -cefalociclidina A, incluida una ciclización radical en etapa tardía.

Conclusiones:

El sistema catalítico desarrollado proporciona una ruta efectiva a los heterociclos N complejos.
El método genera eficientemente estereocentros cuaternarios desafiantes.
Este trabajo ofrece una herramienta valiosa para la síntesis de alcaloides y compuestos relacionados.

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