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Adición eficiente y selectiva catalizada por níquel de enlaces H-P(O) y H-S a los alquinos

Li-Biao Han¹, Chen Zhang, Hideaki Yazawa

¹National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan. libiao-han@aist.go.jp

Journal of the American Chemical Society

|April 22, 2004

Resumen

Los catalizadores de níquel baratos muestran una alta reactividad y selectividad en la adición de enlaces P-O-H y S-H a los alquinos. Se aisló un intermediario clave del complejo de níquel, lo que demuestra el mecanismo catalítico de estas valiosas reacciones de adición.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis de la catálisis.
Química verde es la química verde.

Sus antecedentes:

Los catalizadores de metales nobles se utilizan típicamente para las adiciones a los alquinos.
El desarrollo de catalizadores rentables y eficientes es crucial para la química sostenible.

Objetivo del estudio:

Para investigar la eficacia de los catalizadores de níquel en las adiciones de enlaces P-O-H y S-H a los alquinos.
Para comparar la reactividad de los catalizadores de níquel con los catalizadores de metales nobles.
Para dilucidar el mecanismo catalítico a través del aislamiento de los intermediarios clave.

Principales métodos:

Reacciones de adición catalítica utilizando catalizadores de níquel con varios sustratos y alquinas que contienen P (O) -H y S-H.
Aislamiento y caracterización de un complejo de níquel hidrido de cinco coordenadas.
Reacción del complejo aislado con alquinos para estudiar el mecanismo.

Principales resultados:

Los catalizadores de níquel exhibieron una mayor reactividad que los catalizadores de metales nobles.
Se obtuvieron aductos de Markovnikov y anti-Markovnikov regionales y estereoselectivos en rendimientos altos.
Se aisló y caracterizó con éxito un complejo intermedio de níquel hidrido de cinco coordenadas.
El complejo aislado reaccionó fácilmente con los alquinos, confirmando su papel en el ciclo catalítico.

Conclusiones:

Los catalizadores de níquel de bajo costo son alternativas efectivas a los metales nobles para las adiciones de enlaces P-O-H y S-H a los alquinos.
El estudio proporciona conocimientos mecanicistas sobre la funcionalización del alquino catalizado por níquel.
Este trabajo ofrece un enfoque más ecológico y económico para la síntesis de valiosos aductos.

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