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Metilenospiros[2.3]hexanos por medio de ciclopropanaciones catalizadas por níquel con propelano

Songjie Yu¹, Adam Noble¹, Robin B Bedford¹

¹School of Chemistry , University of Bristol , Cantock's Close , Bristol BS8 1TS , U.K.

Journal of the American Chemical Society

|December 3, 2019

Resumen

La catálisis del níquel (0) transforma el propeleno de alta tensión en un precursor versátil de carbenos. Esto permite la síntesis selectiva de derivados de hexano de metilenospiros a través de la ciclopropanación de alquenos.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

[1.1.1]El propeleno es un hidrocarburo tensado conocido por sus reacciones de adición.
La catálisis de metales de transición del propeleno [1.1.1] está poco desarrollada, produciendo mezclas y una escasa selectividad.
Los métodos existentes carecen de utilidad sintética para diversos derivados de biciclo[1.1.1]pentano.

Objetivo del estudio:

Desarrollar nuevas reacciones catalizadas por metales de transición del propeleno [1.1.1].
Para utilizar el [1.1.1]propelano como precursor del carbeno para la ciclopropanación.
Para sintetizar productos de metilenospiros y hexano con una alta selectividad.

Principales métodos:

Se empleó la catálisis del níquel 0.
Reacción del [1.1.1]propelano con los alquenos funcionalizados.
Se realizaron estudios computacionales para dilucidar el mecanismo de reacción.

Principales resultados:

La catálisis del níquel (0) permitió el uso del propelano [1.1.1] como precursor del carbeno.
Se logró la síntesis selectiva de los productos de hexano metilenospiros.
Los estudios computacionales apoyaron un mecanismo que involucra un complejo de Ni(0) -[1.1.1]propelano y un intermediario de 3-metilenociclobutilideno-níquel.

Conclusiones:

La catálisis del níquel (0) proporciona una nueva utilidad sintética para el propeleno.
Este método ofrece acceso selectivo a los derivados de metilenospiros[2.3]hexano.
El sistema catalítico desarrollado supera las limitaciones de los enfoques anteriores.

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