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Síntesis de alanos y alcinos endocíclicos quirales a través de la adición cíclica dipolar asimétrica de orden

Bin Shi¹, Meng Xiao¹, Jin-Pu Zhao¹

¹Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China.

Journal of the American Chemical Society

|September 18, 2024

Resumen

Este estudio introduce una nueva cicloadición catalizada por el paladio para la síntesis de alenos y alquinos heterocíclicos quirales. El método ofrece altos rendimientos y selectividades, proporcionando una ruta versátil para moléculas complejas.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

Las reacciones catalizadas por el paladio son cruciales en la síntesis orgánica.
El desarrollo de métodos eficientes para los compuestos heterocíclicos quirales sigue siendo un desafío.

Objetivo del estudio:

Desarrollar una nueva cicloadición asimétrica de orden superior catalizada por Pd.
Para sintetizar alenos endocíclicos quirales y alquinas con motivos heterocíclicos de tamaño medio.

Principales métodos:

Utilizando nuevos dipolos de alquileno-π-alil-Pd y π-propargilo-Pd.
Utilizando carbonatos de allenilo y azadienos como socios de la reacción.
La realización de estudios experimentales y computacionales para aclarar el mecanismo.

Principales resultados:

Se ha logrado la síntesis de alenos endocíclicos quirales con altos rendimientos (hasta el 97%) y selectividades (hasta 97:3 er, >19:1 dr).
Amplió la estrategia para sintetizar alquinas endocíclicas de 10 miembros con altos rendimientos (hasta el 98%) y selectividades (hasta 94,5:5,5 er).
Demostró una plataforma modular para la síntesis de moléculas quirales complejas.

Conclusiones:

La cicloadición catalizada por Pd desarrollada es una herramienta poderosa para construir andamios heterocíclicos quirales desafiantes.
Las ideas mecanicistas guiaron el diseño de nuevos sistemas catalíticos para las transformaciones relacionadas.

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