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Una secuencia formal sin precedentes [5 + 2] de cicloadición de nitrones con o-carborina a través del tándem [3 + 2]

Da Zhao¹, Jiji Zhang¹, Zuowei Xie¹

¹Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong , Shatin, N. T., Hong Kong, Hong Kong, China.

Journal of the American Chemical Society

|October 16, 2015

Resumen

Los investigadores desarrollaron una nueva reacción de cicloadición formal [5 + 2] entre nitrones y o-carborinas. Este método sintetiza eficientemente heterociclos complejos de siete miembros fusionados con carborano, expandiendo la química sintética.

Área de la Ciencia:

Química orgánica
Química medicinal
Ciencias de los materiales

Sus antecedentes:

Los compuestos heterocíclicos son andamios cruciales en los productos naturales y farmacéuticos.
Las reacciones de cicloadición ofrecen vías eficientes a arquitecturas moleculares complejas.
Los carboranos son compuestos únicos que contienen boro con diversas aplicaciones.

Objetivo del estudio:

Informar sobre una nueva metodología sintética para la construcción de heterociclos fusionados con carborano.
Explorar la reactividad de las o-carborinas en las reacciones de cicloadición.
Investigar el mecanismo de la nueva cicloadición nitrón-carborina.

Principales métodos:

Reacción de cicloadición formal [5 + 2] entre nitrones y o-carborinas.
Estudios experimentales que incluyen la optimización de la reacción y la caracterización del producto.
Análisis computacional (por ejemplo, cálculos DFT) para dilucidar el mecanismo de reacción.

Principales resultados:

Síntesis exitosa de heterociclos de siete miembros fusionados con carborano.
Identificación de una vía de reacción que incluye [3 + 2] cicloadición, escisión de enlaces N-O, migración de oxígeno y rearomatización.
Demostración de las fracciones de nitrón que actúan como sintetones de cinco átomos que incorporan ambos heteroátomos.

Conclusiones:

Se ha establecido una nueva y sin precedentes [5 + 2] cicloadición formal.
El método desarrollado proporciona acceso a estructuras heterocíclicas únicas que contienen carborano.
Este trabajo ofrece nuevos conocimientos sobre el comportamiento químico de los nitrones y las carborinas.

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