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Isomerización alqueno-carbono inducida por el boro: acceso a un diboreno asimétrico
Wei Lu1, Yongxin Li1, Rakesh Ganguly1
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, and ‡NTU-CBC Crystallography Facility, Nanyang Technological University , 637371, Singapore.
Journal of the American Chemical Society
|March 24, 2017
Resumen
Los investigadores sintetizaron un nuevo compuesto de diboreno utilizando carbonos cíclicos (alquilo) (amino) y boranos. Este estudio revela la naturaleza polarizada del diboreno y su transformación en un derivado de metilenociclopropano que contiene B,N.
Área de la Ciencia:
- Química del organoboron
- Química de los carbenos
- La química de los elementos del grupo principal
Sus antecedentes:
- Los carbenos cíclicos (alquilo) (amino) son ligandos versátiles en la química organometálica.
- Los boranos son especies reactivas a menudo utilizadas en síntesis y catálisis.
- Los diborenos, compuestos que presentan un doble enlace boro-boro, son de gran interés debido a sus propiedades electrónicas únicas.
Objetivo del estudio:
- Desarrollar una nueva vía sintética para los compuestos de diboreno utilizando cAAC.
- Investigar la estructura electrónica y la reactividad de un diboreno asimétrico.
- Explorar la transformación del diboreno en otras estructuras que contienen boro.
Principales métodos:
- Síntesis de un adducto de cAAC-borano mediante la migración de 1,2-hidrógeno.
- Aislamiento y caracterización completa de un diboreno asimétrico (cAAC · Br · B · B · Br · IDip 6).
- Estudios espectroscópicos (11B RMN), de difracción de rayos X y computacionales para analizar las propiedades electrónicas del diboreno.
- Reacción del diboreno con un isonitrile para formar un nuevo compuesto que contiene B,N.
Principales resultados:
- Se sintetizó y caracterizó con éxito un nuevo diboreno asimétrico, cAAC·(Br) BB(Br) ·IDip 6.
- El análisis de la estructura electrónica reveló una fracción polarizada de B2 dentro del diboreno.
- El enlace doble BB en el diboreno podría ser completamente escindido por reacción con un isonitril.
- Se formó un nuevo derivado de metilenociclopropano con B,N estabilizado en bases (7).
Conclusiones:
- La metodología sintética desarrollada permite acceder a nuevas estructuras de diboreno.
- El diboreno asimétrico exhibe una polarización electrónica única, que ofrece oportunidades para nuevos estudios de reactividad.
- La escisión del enlace BB y la formación del derivado metilenociclopropano demuestran la reactividad versátil de los diborenos.
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