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N-heterocíclico carbeno catalizado [3+4] cicloadición y resolución cinética de las iminas de azometina

Ming Wang¹, Zhijian Huang, Jianfeng Xu

¹Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore.

Journal of the American Chemical Society

|January 16, 2014

Resumen

Este estudio introduce la primera reacción de cicloadición catalizada por carbenos [3+4] N-heterocíclicos entre las iminas de azometina y las enals. El nuevo método sintetiza eficientemente heterociclos de siete miembros fundidos con nitrógeno dinitrógeno con alta pureza óptica.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Química Heterocíclica La Química Heterocíclica es una de las más conocidas.

Sus antecedentes:

Los carbenos N-heterocíclicos (NHC, por sus siglas en inglés) son organocatalizadores versátiles.
Las reacciones de cicloadición son fundamentales en la síntesis orgánica para la formación de compuestos cíclicos.
Las iminas y enals de azometina son bloques de construcción clave en la síntesis orgánica.

Objetivo del estudio:

Desarrollar una nueva reacción de cicloadición [3+4] catalizada por el carbeno N-heterocíclico (NHC).
Para sintetizar productos heterocíclicos de siete miembros fundidos con dinitrógeno.
Para lograr la resolución cinética de las iminas de azometina.

Principales métodos:

Utilizando la catálisis NHC para la [3+4] cicloadición de iminas y enals. de azometina.
Empleando la activación oxidativa catalítica remota de enalos para generar intermedios 1,4-dipolarófilos.
Reaccionando estos intermediarios con las iminas de azometina 1,3-dipolar.

Principales resultados:

Se logró la primera cicloadición exitosa [3+4] catalizada por NHC de iminas y enalos de azometina.
Los productos heterocíclicos de siete miembros fusionados con dinitrógeno fueron sintetizados con altas purezas ópticas.
Se demostró una resolución cinética efectiva de las iminas de azometina, resolviendo los centros quirales alejados del catalizador.

Conclusiones:

Este trabajo presenta una nueva ruta sintética para valiosos heterociclos que contienen nitrógeno.
La metodología desarrollada ofrece un alto control estéreo y una amplia aplicabilidad.
La reacción catalizada por NHC proporciona una estrategia eficiente para la resolución cinética en la síntesis asimétrica.

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