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Hidrogenación altamente selectiva de enlaces CC catalizados por un hidruro de rodio

Yiting Gu¹, Jack R Norton¹, Farbod Salahi²

¹Department of Chemistry, Columbia University, 3000 Broadway, New York City, New York 10027, United States.

Journal of the American Chemical Society

|June 18, 2021

Resumen

Un nuevo catalizador de rodio permite la hidrogenación selectiva del enlace C = C en condiciones suaves. Este catalizador homogéneo hidrogena eficientemente varios compuestos insaturados, ofreciendo un enfoque complementario a los métodos existentes.

Área de la Ciencia:

Química organometálica
Catálisis
Síntesis orgánica

Sus antecedentes:

La hidrogenación es una transformación crucial en la síntesis orgánica.
La hidrogenación selectiva de enlaces C = C en compuestos carbonílicos α,β insaturados sigue siendo un desafío, especialmente con sustratos complejos.
Es muy deseable el desarrollo de catalizadores homogéneos eficientes y selectivos.

Objetivo del estudio:

Desarrollar un nuevo catalizador para la hidrogenación selectiva de enlaces C=C.
Para investigar la actividad catalítica en condiciones suaves.
Explorar el alcance y las limitaciones del catalizador con varios sustratos funcionalizados.

Principales métodos:

Síntesis y caracterización del catalizador Cp*Rh(2-(2-piridil) fenil) H.
Reacciones de hidrogenación realizadas en condiciones suaves (temperatura ambiente, 80 psi H2).
Estudios mecanicistas para elucidar la vía de reacción e identificar los productos intermedios.

Principales resultados:

El catalizador Cp*Rh(2-(2-piridil)fenilo) H hidrogena selectivamente el enlace C=C en los compuestos carbonílicos α,β insaturados.
El catalizador es eficaz para los precursores de productos naturales con sustitutos β voluminosos y sustratos con diversos grupos funcionales.
También se observó la hidrogenación de enlaces dobles aislados; no se detectaron radicales intermedios.

Conclusiones:

Cp*Rh(2-(2-piridil)fenilo) H es un catalizador homogéneo muy eficaz para la hidrogenación selectiva del enlace C=C.
El catalizador funciona bajo condiciones suaves y prácticas, lo que lo convierte en una valiosa adición a las metodologías sintéticas.
Este sistema catalítico ofrece una importante complementariedad con los protocolos de hidrogenación existentes.

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