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A B₄N₂ Benzeno de Dewar como un bloque de construcción para las cadenas B,N conjugadas

Kei Ota¹, Rei Kinjo¹

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

Journal of the American Chemical Society

|July 15, 2021

Resumen

Los investigadores sintetizaron el primer benceno de Dewar B4N2 aislado, un nuevo análogo inorgánico del benceno de Dewar. Este nuevo compuesto sirve como un bloque de construcción versátil para crear cadenas conjugadas de boro y nitrógeno.

Área de la Ciencia:

Química inorgánica
Química orgánica
Ciencias de los materiales

Sus antecedentes:

El benceno de Dewar, un isómero de valencia aislable del benceno, ha sido ampliamente estudiado.
La química de los análogos inorgánicos del benceno de Dewar, en particular los que contienen boro y nitrógeno (bencenos B,N-Dewar), está menos desarrollada.
Los benzenos B,N-Dewar existentes están limitados al sistema B3N3.

Objetivo del estudio:

Informar sobre el desarrollo y la síntesis del primer benceno Dewar B4N2 aislable.
Investigar las propiedades estructurales y electrónicas de este nuevo compuesto.
Para explorar su potencial como un bloque de construcción para nuevos materiales.

Principales métodos:

Cálculos de la teoría funcional de la densidad (DFT) para la predicción y el análisis estructural.
Síntesis del benceno de Dewar B4N2 objetivo (3) utilizando una selección juiciosa de sustituyentes.
Espectroscopia de difracción de rayos X de un solo cristal y resonancia magnética nuclear (RMN) para la caracterización estructural.
Reacciones con etileno y fenilacetileno para formar sistemas de anillos fundidos (4 y 5).

Principales resultados:

Síntesis exitosa del primer benceno de Dewar B4N2 aislable (3).
Confirmación de un enlace sigma B(sp3) -B(sp3) situado en la posición de la cabeza de puente.
Reacciones suaves con etileno y fenilacetileno para obtener sistemas de anillos B4C4N2 fundidos (4 y 5).
Caracterización de los compuestos 4 y 5 que revelan un andamio de tetraeno rígido y conjugado (BN) 4.

Conclusiones:

El nuevo B4N2 Dewar benceno (3) ha sido sintetizado y caracterizado con éxito.
Este compuesto posee características estructurales únicas, incluido un enlace sigma de cabeza de puente B-B.
La reactividad de 3 demuestra su utilidad como un bloque de construcción para la construcción de cadenas B, N conjugadas y materiales relacionados.

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