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Radicales organosilicones con enlaces Si-H y Si-Me de los precursores de las materias primas

Subrata Kundu¹, Prinson P Samuel¹, Soumen Sinhababu¹

¹Universität Göttingen , Institut für Anorganische Chemie, Tammannstrasse 4, D-37077 Göttingen, Germany.

Journal of the American Chemical Society

|July 27, 2017

Resumen

Los investigadores aislaron alquil ((amino) carbeno cíclico estable (cAAC) estabilizado de silicio. Estos nuevos compuestos, incluido el primer biradical de SiH2 aislado sin un aceptor, muestran una notable estabilidad a temperatura ambiente.

Área de la Ciencia:

Química del silicio orgánico
Química de los carbenos
La Química Radical

Sus antecedentes:

Los alquil ((amino) carbenos cíclicos (cAAC) son conocidos por estabilizar las especies reactivas.
Los birádicos basados en silicio son difíciles de aislar y caracterizar debido a su alta reactividad.
Los estudios anteriores a menudo requerían moléculas aceptadoras para la estabilización.

Objetivo del estudio:

Síntesis y caracterización de nuevos biradicales que contienen silicio estabilizados por ligandos cAAC.
Investigar las propiedades estructurales y electrónicas de estos birrádicos.
Explorar la posibilidad de aislar los birádicos de silicio sin la necesidad de moléculas aceptoras.

Principales métodos:

En el caso de los compuestos químicos, se recomienda que se utilicen las siguientes combinaciones de compuestos químicos:
Análisis de la estructura de rayos X monocristalino para su determinación estructural.
Espectroscopia de resonancia paramagnética de electrones (EPR) para la caracterización de los radicales.
Métodos computacionales teóricos para el análisis de la estructura y los enlaces.

Principales resultados:

Se han aislado tres especies bi-radicales moleculares estables: (cAAC) 2SiH2 (1), (cAAC) SiMe2-SiMe2 ((cAAC) 2) y (cAAC) SiMeCl-SiMeCl ((cAAC) 3).
Los compuestos 1-3 muestran estabilidad a temperatura ambiente durante más de 6 meses en condiciones inertes.
El compuesto 1 representa el primer aislamiento de una fracción de SiH2 que contiene un biradical sin una molécula aceptora.
Las investigaciones estructurales y de enlace confirmaron la naturaleza birradical y la estabilidad.

Conclusiones:

Los ligandos cAAC estabilizan eficazmente los biradicales basados en silicio, lo que permite su aislamiento como especies moleculares.
El aislamiento exitoso del compuesto 1 demuestra un avance significativo en la estabilización de las especies reactivas de silicio.
Estos hallazgos abren nuevas vías para explorar la química y las aplicaciones de los biradicales de silicio.

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