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Generación de Rh-carbenos del tipo Fischer con los Rh-carbinoides

Eric Palomo^1,2, Akhilesh K Sharma¹, Zhaofeng Wang¹

¹Institute of Chemical Research of Catalonia (ICIQ-CERCA), The Barcelona Institute of Science and Technology, Països Catalans 16, 43007 Tarragona, Spain.

Journal of the American Chemical Society

|February 22, 2023

Resumen

Este estudio introduce el primer método catalítico para generar rodio (II) -carbenos a partir de ácidos carboxílicos. Este avance permite una síntesis eficiente de lactonas complejas fusionadas con ciclopropilo con un alto estereocontrol.

Área de la Ciencia:

Química organometálica
Síntesis orgánica
Catálisis

Sus antecedentes:

El rodio (II) -carbenos son los intermediarios versátiles en la síntesis orgánica.
Los métodos anteriores para generar estas especies tienen limitaciones.

Objetivo del estudio:

Desarrollar un nuevo método catalítico para la generación de aciloxi Rh (II) -carbenos de tipo Fischer.
Explorar la utilidad sintética de estos intermedios en la construcción de moléculas complejas.

Principales métodos:

Generación catalítica de Rh (II) -carbenos a partir de ácidos carboxílicos y Rh (II) -carbinoides.
Las reacciones de ciclopropanación.
Cálculos de la Teoría Funcional de la Densidad (DFT).

Principales resultados:

Generación catalítica exitosa de una nueva clase de donantes/aceptores transitorios de Rh (II) -carbenos.
Acceso a las lactonas densamente funcionalizadas con ciclopropilo a través de la ciclopropanación.
Se obtiene una excelente diastereoselectividad en el proceso de ciclopropanación.

Conclusiones:

El método desarrollado proporciona una nueva vía para obtener estructuras de lactona valiosas.
Los cálculos de DFT aclararon las propiedades de los productos intermedios clave y el mecanismo de reacción.
Este trabajo amplía el conjunto de herramientas para las transformaciones catalíticas de carbenos.

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