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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization

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Reacciones de acoplamiento electrófilo migratorio remoto y hidroarilación de olefinas habilitadas por la generación

Fenglin Chen¹, Ke Chen¹, Yao Zhang¹

¹State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.

Journal of the American Chemical Society

|September 8, 2017

Resumen

Un nuevo método catalizado por níquel permite una síntesis eficiente de 1,1-diarilalcanos utilizando bromuros de alquilo y arilo comunes. Esta estrategia ofrece una ruta versátil a diversas estructuras químicas en condiciones suaves.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Las reacciones de acoplamiento electrofilo cruzado son cruciales para la formación de enlaces C-C.
El desarrollo de métodos eficientes y generales para la síntesis de 1,1-diarilalcanos sigue siendo un desafío importante.

Objetivo del estudio:

Desarrollar una estrategia novedosa y altamente eficiente para el acoplamiento transversal reductivo remoto.
Sintetizar 1,1-diarilalcanos estructuralmente diversos utilizando materiales de partida abundantes y estables.

Principales métodos:

Migración/arilación del níquel controlada por ligando.
Utilizando bromuros de alquilo y bromuros de arilo como socios de acoplamiento.
Utilizando el manganeso (Mn) como fuente potencial de hidrógeno.

Principales resultados:

Se ha logrado la síntesis de una amplia gama de 1,1-diarilalcanos con excelentes rendimientos.
Se han demostrado elevadas regioselectividades en condiciones de reacción suaves.
Se demostró la sustitución del bromuro de alquilo por un intermediario de olefina.

Conclusiones:

El protocolo desarrollado proporciona un método general y eficiente para la síntesis de 1,1-diarilalcanos.
La catálisis de níquel controlada por ligando ofrece una herramienta poderosa para la formación de enlaces C-C.
Esta estrategia amplía el alcance de las reacciones de acoplamiento cruzado electrofilo.

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