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Acoplamiento reductor regioselectivo alquino-alquino a base de alcóxido de titanio mediado por arylamidato generado

Bin Cai¹, James S Panek¹

¹Department of Chemistry, Metcalf Center for Science and Engineering , Boston University , 590 Commonwealth Avenue , Boston , Massachusetts 02215 , United States.

Journal of the American Chemical Society

|February 13, 2020

Resumen

Este estudio introduce una nueva reacción catalizada por titanio para el acoplamiento reductor alquino-alquino. El método logra una alta regioselectividad, formando exclusivamente (E,E) -dienes y demostrando un nuevo efecto de dirección.

Área de la Ciencia:

Química orgánica
Química organometálica
Catálisis

Sus antecedentes:

Las reacciones de acoplamiento reductivo mediadas por metales son cruciales para la formación de enlaces C-C.
El desarrollo de métodos selectivos y eficientes de acoplamiento sigue siendo un área activa de investigación.
Los efectos de grupo dirigidos en la catálisis de metales ofrecen vías para controlar la reactividad y la selectividad.

Objetivo del estudio:

Para describir una nueva reacción de acoplamiento reductor alquino-alquino catalizado por el alcóxido de titanio.
Investigar la regioselectividad y el alcance de esta transformación.
Explorar la influencia potencial de dirección de las funcionalidades de amida y carbamato.

Principales métodos:

Se utilizan precursores de alcóxido de titanio para la generación de sistemas catalíticos.
Se utilizan especies de arylamidato generadas in situ como productos intermedios clave.
Se realizó el acoplamiento reductivo de varios sustratos de alquina.

Principales resultados:

Se ha conseguido la formación exclusiva de (E,E) -dienes en 37 ejemplos.
Se ha demostrado una elevada regioselectividad en el proceso de acoplamiento reductivo.
Se observó un aparente efecto de dirección de los grupos amida y carbamato.

Conclusiones:

El método desarrollado proporciona una ruta eficiente a los dienos (E,E) a través del acoplamiento reductor alquino-alquino.
Este trabajo destaca el primer caso reportado de efectos de dirección de amida y carbamato en tales acoplamientos mediados por metales.
Los resultados abren nuevas vías para el diseño de transformaciones catalíticas selectivas.

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