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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Cicloadición azida-alquina catalizada por rutenio: alcance y mecanismo
Brant C Boren1, Sridhar Narayan, Lars K Rasmussen
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|June 24, 2008
Resumen
Los complejos de rutenio (II) catalizan de manera eficiente las cicloadiciones azida-alquina, produciendo 1,5-disubstituidos y 1,2,3-triazoles totalmente sustituidos. El mecanismo de cicloadición azida-alquina catalizado por rutenio (RuAAC) implica acoplamiento oxidativo y eliminación reductiva.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Síntesis orgánica La síntesis orgánica.
- La catálisis es la catálisis.
Sus antecedentes:
- Los complejos de rutenio son catalizadores versátiles en las transformaciones orgánicas.
- Las cicloadiciones azida-alquina son cruciales para la síntesis de heterociclos que contienen nitrógeno.
Objetivo del estudio:
- Evaluar los complejos de rutenio (II) como catalizadores para las cicloadiciones azida-alquina.
- Explorar el alcance y las limitaciones de la cicloadición azida-alquina catalizada por rutenio (RuAAC).
Principales métodos:
- Cribado de varios complejos [Cp*RuCl], incluyendo Cp*RuCl(PPh3) 2, Cp*RuCl ((COD), y Cp*RuCl ((NBD).
- Reacción de azidas primarias, secundarias y terciarias con alquinos terminales e internos.
- Investigación mecanicista utilizando cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- Cp * RuCl ((PPh3) 2 y Cp * RuCl ((COD) demostraron una alta actividad catalítica.
- Síntesis selectiva de 1,5-disubstituidos 1,2,3-triazoles a partir de azidas primarias/secundarias y alquinas terminales.
- Acceso a los 1,2,3-triazoles completamente sustituidos mediante el uso de alquinas internas.
Conclusiones:
- Los complejos de rutenio (II) son catalizadores efectivos para diversas cicloadiciones azida-alquina.
- La reacción RuAAC procede a través de un mecanismo de acoplamiento oxidativo y eliminación reductiva propuesto.
- Los cálculos de DFT apoyan el mecanismo propuesto, identificando la eliminación reductiva como la determinación de la tasa.
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