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Evaluación experimental y computacional de la reactividad y el mecanismo en la eliminación reductora de formación de

Ian M Pendleton¹, Mónica H Pérez-Temprano¹, Melanie S Sanford¹

¹Department of Chemistry, University of Michigan , Ann Arbor, Michigan 48109, United States.

Journal of the American Chemical Society

|April 19, 2016

Resumen

Este estudio revela nuevas vías para la formación de enlaces C ((sp ((3)) -N en complejos de paladio. Los métodos computacionales y experimentales descubrieron reordenamientos inesperados de ligandos y reacciones SN2, avanzando en la comprensión de la química organometálica.

Área de la Ciencia:

Química organometálica
Química computacional
Elucidación del mecanismo de reacción

Sus antecedentes:

Los complejos de palladio ligado a la sulfonamida son intermediarios clave en la formación de enlaces C-N.
La comprensión del mecanismo de eliminación reductora es crucial para las aplicaciones catalíticas.

Objetivo del estudio:

Investigar el mecanismo de la eliminación reductora formadora de enlaces C ((sp ((3)) -N de los complejos P ((IV)).
Combinar datos experimentales con métodos computacionales avanzados para obtener conocimientos mecanicistas.

Principales métodos:

Evaluación experimental de la reactividad.
El hallazgo de la reacción combinatoria computacional utilizando ZStruct.
Análisis de las vías de reacción en múltiples etapas y de los estados de transición.

Principales resultados:

Se han identificado dos vías de isomerización fáciles para los isómeros Pd (IV).
Descubrió dos vías SN2 competidoras para el acoplamiento C ((sp ((3)) -N.
Se descubrió un intercambio inesperado de oxígeno y nitrógeno en el ligando de la sulfonamida antes de la eliminación reductora.
Las energías libres de activación calculadas (ΔG‡) se alinearon bien con las observaciones experimentales.
Las velocidades de reacción relativas previstas para varios derivados de la sulfonamida.

Conclusiones:

La combinación de enfoques experimentales y computacionales proporciona una comprensión mecanicista fundamental.
Las nuevas herramientas computacionales como ZStruct son valiosas para explorar vías de reacción complejas.
Los hallazgos ofrecen información sobre el control de la formación de enlaces C-N en la catálisis organometálica.

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