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Adición terminal enantioselectiva a las Allenas por catálisis de Amina Primaria Chiral Doble/Palladio

Han Zhou^1,2,3, Yaning Wang^1,2,3, Long Zhang^1,2,3

¹Key Laboratory for Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.

Journal of the American Chemical Society

|February 28, 2017

Resumen

Este estudio introduce un nuevo método catalítico que utiliza aminas primarias quirales y paladio para adiciones enantioselectivas a los allenos. La reacción crea eficientemente moléculas complejas con centros cuaternarios de todo carbono.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

La alquilación alilica asimétrica es crucial para la síntesis de moléculas quirales.
La creación de centros cuaternarios acíclicos de todo carbono sigue siendo un desafío sintético.

Objetivo del estudio:

Desarrollar un nuevo sistema catalítico para la adición terminal enantioselectiva a los alenos.
Para sintetizar adutos alilicos con estereocentros cuaternarios de todo el carbono.

Principales métodos:

Utilizando un sistema de catalizador quiral primario de aminas y achiral de paladio.
Utilizando como nucleófilos los β-cetocarbonilos y aldehídos α-branqueados.
Reaccionan con una amplia gama de alelos terminales, incluidas las variantes alifáticas y 1,1'-disubstituidas.

Principales resultados:

Se ha logrado una elevada regioselectividad y enantioselectividad en las reacciones de adición.
Se han generado con éxito adutos aleloides con centros cuaternarios todo-carbono acíclicos.
Se ha demostrado un amplio alcance del sustrato, alojando varias estructuras de alenos.

Conclusiones:

El método desarrollado proporciona una ruta eficiente a bloques de construcción quirales valiosos.
Amplia la utilidad de las reacciones asimétricas de alquilación.
Ofrece un enfoque versátil para la construcción de arquitecturas moleculares complejas.

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