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Efectos de los ligandos y sustratos en las hidroaciloxilaciones regionales y estereoselectivas de Ru (II) catalizadas

Paul A Beasley¹, Frank E McDonald¹

¹Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States of America.

Advanced synthesis & catalysis

|August 26, 2025

Resumen

Dos sistemas catalíticos de rutenio permiten las hidroaciloxilaciones regioselectivas anti-Markovnikov de las alquinas terminales. Los diferentes complejos de rutenio producen selectivamente isómeros de éster vinílico (E) o (Z).

Área de la Ciencia:

Química organometálica
Síntesis orgánica

Sus antecedentes:

La hidroaciloxilación de alquinas es una transformación clave para sintetizar ésteres vinílicos.
El control de la regioselectividad y la estereoselectividad en la funcionalización de las alquinas sigue siendo un desafío importante en la síntesis orgánica.

Objetivo del estudio:

Desarrollar nuevos sistemas catalizados por rutenio para la hidroaciloxilación regioselectiva anti-Markovnikov de las alquinas terminales.
Para lograr la síntesis estereoselectiva de los ésteres vinílicos (E) y (Z).

Principales métodos:

Se utilizaron dos sistemas catalíticos distintos de rutenio: [Ru] [NCCH3] [BF4] y un complejo de escorpionato de rutenio con ligandos que extraen electrones.
Investigó la reacción de alquinas terminales con varios ácidos carboxílicos bajo las condiciones catalíticas desarrolladas.

Principales resultados:

El sistema [Ru(NCCH3) [6][(BF4) 2 demostró una alta selectividad para los ésteres (E) vinílicos cuando se utilizaron arylacetilenos y ácidos carboxílicos seleccionados.
El complejo de escorpionato de rutenio produjo selectivamente isómeros de éster vinílico (Z).

Conclusiones:

Desarrolló dos sistemas catalíticos complementarios de rutenio para la síntesis estereoselectiva de ésteres vinílicos a través de la hidroaciloxilación de Markovnikov.
Se ha demostrado la capacidad de controlar el resultado estereoquímico ((E) o (Z) isómero) mediante la elección juiciosa del catalizador de rutenio.

Palabras clave:

Alquinas y sus derivados Ácidos carboxílicos El rutenio Ligandos de los trípodos Ligandos de vinilideno

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