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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
N-alquilación catalizada por rutenio de aminas y sulfonamidas utilizando la metodología de préstamo de hidrógeno
M Haniti S A Hamid1, C Liana Allen, Gareth W Lamb
1Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom.
Journal of the American Chemical Society
|February 5, 2009
Resumen
Los catalizadores de rutenio permiten una eficiente alquilación de aminas utilizando alcoholes, convirtiendo las aminas primarias en secundarias y las secundarias en terciarias. Este método también facilita la heterociclado de N y la alquilación de sulfonamidas, ofreciendo una vía sintética versátil.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- La alquilación de aminas es una transformación fundamental en la síntesis orgánica.
- El desarrollo de métodos catalíticos eficientes y selectivos para la alquilación de aminas sigue siendo un área activa de investigación.
- Los métodos tradicionales a menudo implican reactivos agresivos o múltiples pasos.
Objetivo del estudio:
- Desarrollar un nuevo sistema catalítico para la alquilación directa de aminas utilizando alcoholes.
- Explorar el alcance y las limitaciones de este sistema catalítico para varios sustratos de aminas y alcoholes.
- Para demostrar la utilidad de este método en la síntesis de compuestos farmacéuticamente relevantes.
Principales métodos:
- Utilizando un complejo de rutenio, específicamente [Ru(p-cymene) Cl2]2, en combinación con ligandos de fosfina bidentados (dppf o DPEphos).
- El uso de alcoholes como agentes alquilantes para aminas primarias y secundarias.
- Investigando la N-heterociclado de aminas primarias y la alquilación de sulfonamidas primarias.
Principales resultados:
- Conversión exitosa de aminas primarias a aminas secundarias y de aminas secundarias a aminas terciarias.
- Síntesis de importantes compuestos farmacéuticos, incluidos el piribedil, la tripelenamina y la clorfeniramina.
- Eficacia demostrada con alcoholes primarios y secundarios, aunque los alcoholes secundarios requieren condiciones más rigurosas.
Conclusiones:
- El sistema catalizado por rutenio desarrollado proporciona una ruta eficiente para la alquilación de aminas con alcoholes.
- La metodología es versátil, aplicable a la N-heterociclado y la funcionalización de la sulfonamida.
- Este enfoque ofrece una alternativa más ecológica y más económica para el átomo a los métodos de alquilación tradicionales.
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