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Pruebas experimentales de Pd ((NHC) como catalizador competente en el acoplamiento cruzado C-N (NHC = DiMeIHept^Cl)

Volodymyr Semeniuchenko^1,2, Sepideh Sharif³, Neha Rana³

¹Centre for Catalysis Research and Innovation (CCRI), Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.

Journal of the American Chemical Society

|October 10, 2024

Resumen

El nuevo ligando DiMeIHeptCl estabiliza los intermediarios clave de paladio para las reacciones de acoplamiento cruzado C-N. Esta investigación detalla el aislamiento y la caracterización de estos complejos estables de paladio, avanzando en la química catalítica.

Área de la Ciencia:

Química organometálica
Catálisis

Sus antecedentes:

Las reacciones de acoplamiento cruzado C-N catalizadas por paladio son cruciales en la síntesis orgánica.
La estabilización de los intermediarios reactivos de paladio es esencial para una catálisis eficiente.

Objetivo del estudio:

Sintetizar y caracterizar nuevos complejos de palladio-N-heterocíclicos (NHC).
Investigar el papel de un ligando NHC estérico exigente en la estabilización de los intermedios de paladio para el acoplamiento cruzado C-N.

Principales métodos:

Síntesis y caracterización estructural de complejos de paladio utilizando el ligando DiMeIHeptCl.
Aislamiento y caracterización de los intermediarios de paladio cerovalente y divalente.
Investigación de las vías de activación del catalizador y de la adición oxidativa.

Principales resultados:

Aislamiento y caracterización estructural de los complejos de paladio cerovalentes estables ([Pd(DiMeIHeptCl) 2 ((μ-N2), [Pd ((DiMeIHeptCl) 2 ((μ-η2-1,2-η2-4,5-C6H6), Pd ((DiMeIHeptCl) ((piridina)).
Aislamiento y caracterización de los complejos divalentes de paladio (PdCl ((Ph)) ((DiMeIHeptCl), PdCl ((Ph)) ((DiMeIHeptCl)) ((n-propilamina)).
Un complejo de 14 electrones Pd demostró una estabilidad excepcional debido a las interacciones de dispersión.

Conclusiones:

El ligando NHC ramificado DiMeIHeptCl estabiliza efectivamente los intermediarios reactivos del paladio.
La comprensión de estos intermedios proporciona información sobre los mecanismos de activación del catalizador para el acoplamiento cruzado C-N catalizado por Pd.

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