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La fotosensibilización permite reacciones de tipo Pauson-Khand con los nitrenos

Fang Li¹, W Felix Zhu^1,2, Claire Empel¹

¹RWTH Aachen University, Institute of Organic Chemistry, Landoltweg 1, D-52074 Aachen, Germany.

Science (New York, N.Y.)

|February 1, 2024

Resumen

Los químicos desarrollaron una nueva reacción de cicloadición utilizando nitrenos (unidad N1) en lugar de monóxido de carbono (CO). Este método crea compuestos cíclicos, útiles para el descubrimiento y la funcionalidad de los fármacos.

Área de la Ciencia:

Química orgánica
Química sintética
Química medicinal

Sus antecedentes:

La reacción de Pauson-Khand es una reacción de cicloadición ampliamente utilizada, que típicamente emplea monóxido de carbono (CO) como un bloque de construcción C1.
Los métodos de cicloadición existentes tienen una capacidad limitada para incorporar átomos de nitrógeno como unidades N1.

Objetivo del estudio:

Desarrollar reacciones de cicloadición análogas utilizando nitrenos como bloques de construcción de N1.
Sintetizar nuevos compuestos bicíclicos y explorar su potencial como bioisósteros de heterociclos saturados comunes.

Principales métodos:

Utilizó una nueva reacción de cicloadición que involucra dienos no conjugados y precursores de nitreno.
Se llevaron a cabo estudios mecanicistas experimentales y computacionales para dilucidar la vía de reacción.
Aplicó la metodología desarrollada para la funcionalización en etapa tardía de compuestos farmacológicos.

Principales resultados:

Se demostraron con éxito reacciones de cicloadición con nitrenos como unidades N1, análogas a la reacción de Pauson-Khand.
Bioisósteros bicíclicos sintetizados de heterociclos saturados como la piperidina, la morfolina y la piperazina.
Los estudios mecanicistas confirmaron la transmisión del carácter diradical del nitreno triplet en el sistema π.

Conclusiones:

La cicloadición desarrollada a base de nitrógeno ofrece una nueva vía para sintetizar heterociclos que contienen nitrógeno.
La reacción es valiosa para la funcionalización en etapa tardía en el descubrimiento y desarrollo de fármacos.
Se han identificado posibles inhibidores de la epoxida hidrolasa solubles utilizando este nuevo enfoque sintético.

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