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Síntesis asimétrica catalítica de los metaciclos de zinc

Hayden D Bishop¹, Qiang Zhao¹, Christopher Uyeda¹

¹Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.

Journal of the American Chemical Society

|September 11, 2023

Resumen

Este estudio introduce una nueva vía para la síntesis de aminas alilicas quirales mediante catálisis de metales de transición. Se forma un intermediario del ciclo del zinc, lo que permite reacciones de acoplamiento versátiles y expande las posibilidades sintéticas.

Área de la Ciencia:

Química orgánica
Catálisis
Química organometálica

Sus antecedentes:

El acoplamiento reductor catalizado por metales de transición de alquinas e iminas es crucial para la síntesis de aminas alelicas quirales.
Los métodos actuales a menudo implican la ciclización oxidativa seguida de hidrogenólisis de un intermediario metálico.
Existe la necesidad de vías alternativas que ofrezcan una mayor versatilidad sintética.

Objetivo del estudio:

Explorar una vía mecanicista alternativa para el acoplamiento reductor catalizado por metales de transición de alquinos e iminas.
Demostrar la utilidad de un nuevo intermediario de organozinco generado por transmetación.
Ampliar las aplicaciones sintéticas de las reacciones de acoplamiento reductivo.

Principales métodos:

Reacciones catalizadas por metales de transición investigadas que involucran alquinos e iminas.
Utilizó experimentos de etiquetado isotópico para sondear los mecanismos de reacción.
Utilizó cálculos de la Teoría Funcional de la Densidad (DFT) para aclarar los pasos clave.
Se ha caracterizado el intermediario del ciclo del metal organozinc.

Principales resultados:

Se ha demostrado que puede producirse transmitación al zinc, formando un ciclo metálico de zinc.
El producto organozinc actúa como un nucleófilo versátil en las reacciones de acoplamiento posteriores.
Los estudios mecanicistas confirmaron que el paso clave de transmitación involucra una especie de cobalto (II) y cloruro de zinc (ZnCl2).

Conclusiones:

Se ha establecido una nueva vía sintética para las aminas alelicas quirales a través de un intermediario del ciclo del zinc.
Este intermedio organozinc ofrece una amplia aplicabilidad en la formación de enlaces C-C y C-heteroatomo.
Los hallazgos proporcionan nuevos conocimientos mecanicistas sobre las reacciones de acoplamiento reductor catalizadas por metales de transición.

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