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Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
Guanidinophosphazenes: diseño, síntesis y basicidad en THF y en la fase gaseosa
Alexander A Kolomeitsev1, Ilmar A Koppel, Toomas Rodima
1Institute of Inorganic & Physical Chemistry, University of Bremen, Leobener Strasse, D-28334 Bremen, Germany. kolomeit@chemie.uni-bremen.de
Journal of the American Chemical Society
|December 15, 2005
Resumen
Los investigadores desarrollaron un nuevo principio para crear superbasas no iónicas mediante la unión de grupos de guanidino a las bases de fosfazeno. Esto mejora significativamente la resistencia de la base, con aumentos potenciales de más de 40 órdenes de magnitud para futuros diseños de superbases.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis de las superbases.
- Química computacional es la química computacional.
Sus antecedentes:
- Las superbases no iónicas son cruciales en la síntesis orgánica.
- Las superbases existentes tienen limitaciones en cuanto a fuerza y alcance.
- La química de los fosfazenos ofrece una plataforma para el desarrollo de nuevas superbases.
Objetivo del estudio:
- Presentar un nuevo principio para la creación de superbases no iónicas.
- Para sintetizar y caracterizar nuevas superbases basadas en fosfazenos.
- Para evaluar la mayor basicidad de estos nuevos compuestos.
Principales métodos:
- Síntesis de fosfazenos sustituidos por guanidino.
- Titación espectrofotométrica en THF para la determinación de la fuerza de la base.
- Cálculos de la teoría funcional de densidad de alto nivel para la basicidad de la fase gaseosa.
- Cristalografía de rayos X para el análisis estructural.
Principales resultados:
- Se sintetizaron siete nuevas bases de fosfazeno superbásico no iónico.
- La sustitución de tetrametilguanidino aumentó la fuerza de la base en 10 órdenes de magnitud en THF.
- Los cálculos predicen aumentos potenciales de basicidad superiores a 40 órdenes de magnitud para nuevas estructuras.
- Se determinaron las estructuras cristalinas de los compuestos clave.
Conclusiones:
- La unión de grupos de guanidino a los fosfazenos es un principio muy eficaz para crear potentes superbasas no iónicas.
- Esta estrategia ofrece un camino hacia las superbases con una basicidad sin precedentes.
- Los hallazgos abren nuevas vías para el diseño de catalizadores y reactivos avanzados en química.
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