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Reacción enantioselectiva intramolecular Dearomativa Heck catalizada por el paladio

Xiang Li¹, Bo Zhou¹, Run-Ze Yang¹

¹College of Chemical Engineering, State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology , Zhejiang University of Technology , Chaowang Road 18# , Hangzhou 310014 , China.

Journal of the American Chemical Society

|September 27, 2018

Resumen

Las nuevas reacciones catalizadas por el paladio permiten la síntesis enantioselectiva de heterociclos complejos y heterociclos benzofusionados. Estos métodos crean valiosos compuestos quirales con alta estereoselectividad, expandiendo las posibilidades sintéticas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Las reacciones de Heck dearomativas intramoleculares ofrecen una vía a andamios heterocíclicos complejos.
El desarrollo de variantes enantioselectivas es crucial para acceder a moléculas quirales con una estereoquímica definida.

Objetivo del estudio:

Para desarrollar nuevas reacciones enantioselectivas intramoleculares dearomativas de Heck.
Sintetizar heterociclos espiróticos y heterociclos benzofusionados estructuralmente únicos con estereocentros cuaternarios de carbono sustituidos por N/O.

Principales métodos:

Acoplamiento cruzado catalizado por paladio de haluros de arilo/triflatos con enlaces internos C=C de heterociclos (indoles, furanos, etc.) No obstante, la Comisión
Se utilizaron ligandos de fosforamidita de nueva síntesis basados en BINOL y H8-BINOL y (S) -SEGPHOS.

Principales resultados:

Se obtienen rendimientos de moderados a excelentes con enantioselectividades de buenas a excelentes.
Sintetizó diversos espiroheterociclos y heterociclos benzofusionados con estereocentros cuaternarios y olefinas exocíclicas.
Utilidad sintética demostrada a través de hidrogenación, hidroborilación y reordenamientos de expansión de anillos sin pérdida de enantiopureza.

Conclusiones:

Estableció un protocolo eficiente para la síntesis enantioselectiva de valiosos compuestos heterocíclicos.
Destacó el amplio alcance y la aplicabilidad sintética de la metodología desarrollada.
Se han identificado ligandos quirales efectivos para andamios heterocíclicos específicos.

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