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La anulación aeróbica [3+2] catalizada por el cobre de las amidinas N-alquenilo

Yi-Feng Wang¹, Xu Zhu, Shunsuke Chiba

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

Journal of the American Chemical Society

|February 3, 2012

Resumen

Una nueva reacción catalizada por el cobre sintetiza amidinas cíclicas a partir de amidinas N-alquenilo. Estos compuestos pueden reducirse aún más a valiosas y protegidas diaminas vecinas, expandiendo las aplicaciones de la química sintética.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La síntesis de amidina es crucial para los productos farmacéuticos y los materiales.
El desarrollo de rutas sintéticas eficientes y sostenibles es un desafío continuo.
Las amidinas cíclicas ofrecen motivos estructurales únicos para una mayor funcionalidad.

Objetivo del estudio:

Desarrollar una nueva reacción de anulación aeróbica [3+2] catalizada por cobre para sintetizar amidinas bicíclicas y tricíclicas.
Explorar la utilidad de las amidinas cíclicas sintetizadas en transformaciones posteriores.
Establecer una nueva vía para el acceso a las minas de diamantes vecinas protegidas.

Principales métodos:

La anulación aeróbica [3+2] catalizada por el cobre de las amidinas N-alquenilo.
Reducción de las amidinas cíclicas utilizando hidruro de aluminio.
Caracterización de compuestos sintetizados mediante técnicas espectroscópicas.

Principales resultados:

Con éxito sintetizó una gama de amidinas bi y tricíclicas a través del método desarrollado.
Demostró la conversión de estas amidinas cíclicas en diaminas vicinales protegidas por mono-benzil.
Se logran altos rendimientos y selectividad en las etapas de anulación y reducción.

Conclusiones:

La anulación aeróbica [3+2] catalizada por cobre desarrollada proporciona una ruta eficiente a las amidinas cíclicas.
Las amidinas cíclicas sintetizadas sirven como precursores versátiles para las diaminas vicinales protegidas.
Esta metodología ofrece una valiosa adición al kit de herramientas del químico sintético para la construcción de complejos heterociclos que contienen nitrógeno.

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