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Los cationes de sililpalladio permiten la adición oxidativa de enlaces C

Andreas L Wierschen¹, Neyen Romano¹, Stephen J Lee²

¹Caudill Laboratories, Department of Chemistry , The University of North Carolina at Chapel Hill , Chapel Hill , North Carolina 27599-3290 , United States.

Journal of the American Chemical Society

|September 19, 2019

Resumen

Los nuevos cationes de sililpalladio son estables a temperatura ambiente y en solución. Estos complejos pueden dividir enlaces C-O en éteres, actuando como fuentes de iones de silicio y complejos de paladio.

Área de la Ciencia:

Química organometálica
Catálisis
Química del silicio

Sus antecedentes:

Los complejos de sililpalladio son importantes intermediarios en la catálisis.
El desarrollo de especies estables y reactivas de sililpalladio es crucial para el avance de las aplicaciones catalíticas.

Objetivo del estudio:

Síntesis y caracterización de nuevos cationes de sililpalladio estables a temperatura ambiente.
Investigar la reactividad de estos cationes de sililpalladio, en particular en la escisión de enlaces C-O.

Principales métodos:

Síntesis de cationes de sililpalladio con diferentes ligandos de la fosfina (PCy3 y Xantphos).
Caracterización mediante métodos espectroscópicos.
Experimentos de adición de ligandos para determinar la geometría compleja.
Reacciones con éteres dialquilo para estudiar la escisión del enlace C-O.

Principales resultados:

Síntesis y caracterización exitosas de cationes sililpaladio estables: (PCy3) 2Pd-SiR3+ y (Xantphos) Pd-SiR3+.
Los datos espectroscópicos indican una geometría en forma de T de tres coordenadas para los complejos (PCy3) 2Pd-SiR3+.
La adición de éteres dialquilo conduce a la escisión del enlace C ((sp3) -O y la formación de complejos catiónicos Pd-alquilo.

Conclusiones:

Los cationes de sililpalladio son reactivos versátiles capaces tanto de transferencia de iones de silicio electrófilo como de transferencia de paladio nucleófilo.
Estos hallazgos abren nuevas vías para las transformaciones catalíticas que involucran silicio y paladio.

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