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Las jaulas tetraédricas atrapadas cinéticamente a través de la metátesis de alquinos

Semin Lee¹, Anna Yang¹, Timothy P Moneypenny¹

¹Department of Chemistry and The Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.

Journal of the American Chemical Society

|February 9, 2016

Resumen

Las trampas cinéticas en síntesis covalente dinámica pueden producir inesperadamente productos complejos. Este estudio muestra que las jaulas tetraédricas formadas a través de la metástasis de alquina quedan atrapadas cinéticamente, evitando reacciones adicionales y permitiendo la formación de productos de alta pureza.

Área de la Ciencia:

Química supramolecular
Síntesis orgánica

Sus antecedentes:

La química covalente dinámica (DCC) generalmente tiene como objetivo el equilibrio termodinámico.
Las trampas cinéticas a menudo se ven como limitaciones en DCC, evitando la formación de productos.
El logro de estructuras complejas con altos rendimientos sigue siendo un desafío en DCC.

Objetivo del estudio:

Investigar el papel del atrapamiento cinético en la síntesis covalente dinámica.
Para demostrar la formación de estructuras supramoleculares complejas a través del control cinético.
Para explorar la metástasis de alquina como una herramienta para el DCC controlado cinéticamente.

Principales métodos:

Se utilizaron precursores tritópicos para la síntesis en jaula.
Empleó metástasis de alquinos para la formación dinámica de enlaces covalentes.
Se verificó experimentalmente la estabilidad cinética de las jaulas formadas.

Principales resultados:

Se ha conseguido una preparación casi cuantitativa de las jaulas tetraédricas.
Se demostró que las jaulas sintetizadas están atrapadas cinéticamente, sin más intercambio de vértices.
Demostró que el atrapamiento cinético puede conducir a altos rendimientos de productos complejos.

Conclusiones:

Las trampas cinéticas no siempre son desventajosas en la síntesis covalente dinámica.
Los productos atrapados cinéticamente pueden ser valiosos para lograr altos rendimientos de arquitecturas moleculares complejas.
La metátesis de alquinos proporciona una ruta viable para los productos covalentes dinámicos controlados cinéticamente.

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