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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

Published on: March 24, 2018

Efectos sustitutivos en el enlace halógeno [N-I-N]

Anna-Carin C Carlsson¹, Krenare Mehmeti¹, Martin Uhrbom¹

¹Department of Chemistry and Molecular Biology, University of Gothenburg , SE-412 96 Gothenburg, Sweden.

Journal of the American Chemical Society

|June 7, 2016

Resumen

La densidad de electrones tiene un impacto significativo en la estabilidad de los enlaces halógenos [N-I-N] , con una mayor densidad de electrones que mejora la estabilidad. Este hallazgo es crucial para controlar la reactividad de los reactivos sintéticos de tipo [bis ((piridina) halógeno)) ((+)).

Área de la Ciencia:

Química supramolecular
Enlace halógeno
Síntesis orgánica

Sus antecedentes:

El enlace halógeno [N-I-N] es una interacción clave en varios sistemas químicos.
La comprensión de los efectos electrónicos en los enlaces halógenos es crucial para el diseño de reactivos sintéticos.

Objetivo del estudio:

Para investigar cómo la densidad de electrones influye en el enlace halógeno [N-I-N]
Explorar la relación entre los efectos sustitutivos y las propiedades de los enlaces halógenos.

Principales métodos:

Síntesis de [bis (pyridine) iodine] (pyridine) y complejos relacionados sustituidos.
Estudios espectroscópicos que incluyen (15) RMN y cinética UV.
Métodos computacionales (DFT) y difracción de rayos X de un solo cristal.

Principales resultados:

Variación sistemática de la densidad de electrones de nitrógeno de piridina confirmada por RMN (15) y análisis computacional.
La formación de enlaces halógenos [N-I-N] resultó en cambios significativos en la coordinación de la RMN (15).
El aumento de la densidad de electrones en el aceptor de enlace halógeno estabiliza el enlace [N·I·N] , mientras que la deficiencia de electrones reduce la estabilidad.

Conclusiones:

El enlace halógeno [N-I-N] es estático y simétrico, independientemente de la densidad de electrones.
La densidad de electrones afecta principalmente a la estabilidad del enlace halógeno, no a la longitud del enlace N-I.
La modulación de la densidad de electrones ofrece un método para controlar la reactividad de los reactivos de tipo [bis ((piridina) halógeno)) ((+)).

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