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Inducción de la reactividad nucleofílica en el berilio con un ligando de aluminio

Josef T Boronski¹, Lewis R Thomas-Hargreaves², Mathias A Ellwanger¹

¹Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, United Kingdom.

Journal of the American Chemical Society

|February 14, 2023

Resumen

Se sintetizaron nuevos compuestos de berilio-aluminio y berilio-gallio. El enlace berilio-aluminio exhibe un atractor no nuclear único, lo que sugiere una nueva reactividad para las moléculas que contienen berilio.

Área de la Ciencia:

Química organometálica
Química del grupo principal
Química inorgánica

Sus antecedentes:

Los complejos de berilio con elementos del grupo principal son raros.
La comprensión de la unión en los primeros complejos metálicos de transición es crucial.

Objetivo del estudio:

Sintetizar y caracterizar nuevos compuestos de berilio-aluminio y berilio-gallio.
Investigar la estructura electrónica y la unión del enlace Be-Al.
Explorar la reactividad del complejo de berilio-aluminilo sintetizado.

Principales métodos:

Reacción de los nucleófilos aniónicos de aluminio y galio con el beriloceno.
Cristalografía de rayos X para la determinación estructural.
Cálculos químicos cuánticos para el análisis de la estructura electrónica.

Principales resultados:

Formación de complejos (NON) AlBeCp y (NON) GaBeCp.
Observación de un enlace Be-Al significativamente corto (2.310(4) Å) en el complejo berilio-aluminilo.
Identificación de un atractor no nuclear (NNA) para la interacción Be-Al, el primero para una interacción heteroatómica en un complejo molecular aislado.
La carga positiva calculada en Be (+1.39) es menor que en Al (+1.88), lo que sugiere un carácter nucleófilo en Be.
El complejo berilio-aluminilo reacciona con el N,N'-diisopropilcarbodiimida a través del ataque nucleófilo por berilio.

Conclusiones:

El estudio informa el primer ejemplo de un atractor no nuclear en una interacción heteroatómica dentro de un complejo molecular aislado.
La estructura electrónica única del complejo berilio-aluminilo permite el comportamiento nucleófilo en el centro del berilio.
Esta reactividad abre nuevas vías para sintetizar nuevos compuestos que contienen berilio.

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