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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Especies oligoméricas similares al carbocatión por la protonación de los cloroalcanes
Evgenii S Stoyanov1, Irina V Stoyanova, Christopher A Reed
1Department of Chemistry, University of California, Riverside, California 92521-0403, USA. evgeniis@ucr.edu
Journal of the American Chemical Society
|May 17, 2011
Resumen
El ácido carborano H ((CHB ((11) Cl ((11)) protona el cloroetano, formando el etilcarborano e iniciando un proceso de oligomerización. El calentamiento convierte los productos en sales estables de tert-butilo catión carborano.
Área de la Ciencia:
- Química del estado sólido.
- La catálisis por superácido.
- Química organometálica de las sustancias orgánicas.
Sus antecedentes:
- Los ácidos carboranos son súper ácidos sólidos excepcionalmente fuertes.
- Comprender las interacciones superacidas con los haloalcanos es crucial para la catálisis.
- Estudios previos carecían de conocimientos mecanicistas detallados sobre la protonación del cloroetano.
Objetivo del estudio:
- Para investigar la protonación del cloroetano por el ácido carborano.
- Para dilucidar el mecanismo de reacción e identificar los intermediarios.
- Para caracterizar los productos de la oligomerización del cloroetano.
Principales métodos:
- La espectroscopia cuantitativa de infrarrojos (IR) también se conoce como espectroscopia cuantitativa.
- El uso de cloroetano deuterado (d(5) para el seguimiento mecánico.
- El análisis del balance de masas analiza el balance de masas.
Principales resultados:
- Observación de una especie intermedia de EtCl · H ((CHB ((11) Cl ((11)).
- Formación de etilcarborano a través de la eliminación rápida de HCl.
- Identificación de un proceso de oligomerización que produce carboranos de alquilo hasta n=4.
- De-oligomerización y conversión final a la sal de tert-butilo catión carborano después del calentamiento.
Conclusiones:
- La reacción procede a través de distintos intermedios y pasos de eliminación de HCl.
- Una eliminación de HCl no reconocida anteriormente conduce a la oligomerización.
- Los ácidos carboranos facilitan las complejas transformaciones de los haloalcanos.
- Los productos finales son notablemente estables sales de tert-butilo catión carborano.
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