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Anulaciones catalizadas por el paladio de Allenes cíclicos tensados

Andrew V Kelleghan¹, Dominick C Witkowski¹, Matthew S McVeigh¹

¹Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States.

Journal of the American Chemical Society

|June 18, 2021

Resumen

Este estudio introduce una nueva reacción catalizada por el paladio para crear compuestos heterocíclicos fundidos a partir de alenos cíclicos y haluros de arilo. Este método permite una síntesis eficiente de moléculas complejas, incluidas las rutas enantioselectivas.

Área de la Ciencia:

Química orgánica
Catálisis
Metodología sintética

Sus antecedentes:

Los alenos cíclicos son intermedios reactivos a menudo atrapados por nucleófilos o cicloadiciones.
La catálisis de metales de transición ofrece estrategias alternativas para involucrar a los intermediarios tensados.
El desarrollo de nuevas rutas sintéticas para andamios heterocíclicos complejos es crucial en la química medicinal.

Objetivo del estudio:

Desarrollar una metodología de anulación catalizada por paladio para alenos cíclicos tensados generados in situ.
Para sintetizar productos heterocíclicos fundidos utilizando haluros de arilo y precursores de aleno cíclico.
Establecer las variantes diastereoselectivas y enantioselectivas de la reacción de anulación.

Principales métodos:

Reacciones de anulación catalizadas por el paladio.
Utilización de alenos cíclicos tensados generados in situ.
Utilizando haluros de arilo y precursores de aleno cíclico.
Estrategias de síntesis diastereoselectivas y enantioselectivas.

Principales resultados:

Síntesis exitosa de productos heterocíclicos fundidos.
Formación de dos nuevos enlaces y un centro sp3 durante la anulación.
Demostración de las vías de reacción tanto diastereoselectivas como enantioselectivas.
Síntesis enantioselectiva rápida de un producto hexacíclico complejo.

Conclusiones:

La metodología desarrollada proporciona un enfoque novedoso para la funcionalización cíclica del alleno.
Este trabajo amplía el alcance de las reacciones catalizadas por metales de transición que involucran intermedios tensados.
Se espera que los hallazgos inspiren nuevas investigaciones en la fusión de catálisis con química intermedia transitoria para la síntesis de moléculas complejas.

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