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Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

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Pruebas directas de un intermediario de cobre dinuclear en las cicloadiciones azida-alquina catalizadas por Cu (I)

B T Worrell¹, J A Malik, V V Fokin

¹Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA.

Science (New York, N.Y.)

|April 6, 2013

Resumen

La cicloadición azida-alquina catalizada por cobre (I) requiere un catalizador externo para la reactividad. Los experimentos cruzados revelan un mecanismo escalonado y átomos de cobre equivalentes en el proceso de cicloadición.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Mecanismos de reacción Mecanismos de reacción

Sus antecedentes:

La cicloadición azida-alquina catalizada por el cobre es vital para la síntesis de moléculas complejas.
El mecanismo de reacción es complejo debido a múltiples equilibrios y reactivos intermedios.

Objetivo del estudio:

Para dilucidar el mecanismo de la cícloadición azida-alquina catalizada por el cobre.
Para investigar el papel de los complejos de acetílidos de cobre y los catalizadores exógenos.

Principales métodos:

Monitoreo en tiempo real utilizando calorimetría de reacción de flujo de calor.
Experimentos cruzados que utilizan fuentes de cobre enriquecido isotópicamente.

Principales resultados:

Los complejos monoméricos de acetiluro de cobre no reaccionan con las azidas orgánicas sin un catalizador añadido.
Se observó la formación gradual de enlaces carbono-nitrógeno y átomos de cobre equivalentes en la cicloadición.

Conclusiones:

Los catalizadores de cobre exógenos son esenciales para la reactividad de los complejos de acetílido de cobre en las cicloadiciones.
La reacción procede a través de pasos distintos que involucran átomos de cobre equivalentes.

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