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Síntesis catalizada por paladio de sales de 1-alquilfosfonio a partir de 1-alquenos
Mieko Arisawa1, Masahiko Yamaguchi
1Department of Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Sendai 980-8578, Japan.
Journal of the American Chemical Society
|January 5, 2006
Resumen
Una nueva reacción catalizada por el paladio sintetiza eficientemente sales de alquilfosfonio a partir de alquenos, triarilfosfinas y ácidos próticos. Este método ofrece una vía de alto rendimiento para crear valiosos compuestos organofosforados.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis de la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Las sales de fosfonio son versátiles intermediarios en la síntesis orgánica.
- Los métodos catalíticos eficientes para su preparación son muy buscados.
- La catálisis de paladio ofrece una poderosa herramienta para la formación de enlaces C-P.
Objetivo del estudio:
- Desarrollar un nuevo método catalizado por paladio para la síntesis de sales de 1-alquilfosfonio.
- Para investigar la reacción de los alquenos, las triarilfosfinas y los ácidos próticos.
- Explorar el alcance y las limitaciones de esta nueva ruta sintética.
Principales métodos:
- Utilizó un complejo de paladio ((0)), Pd2 ((dba) 3.CHCl3, como el catalizador.
- Alquenos terminales reaccionados (etileno, propeno, 1-buteno) con trifenilfosfina y bis ((trifluorometano sulfonil) imida ((CF3SO2) 2NH).
- Empleado el clorobenzeno como disolvente a 65°C.
Principales resultados:
- Se han logrado altos rendimientos aislados para las sales de etilfosfonio (98%), 1-propilfosfonio (95%) y 1-butilofosfonio (92%).
- Se observó la isomerización de olefinas competidoras con 1-buteno.
- Eficacia demostrada con alquenos menos reactivos utilizando tris ((p-clorofenil) fosfina y altos rendimientos para las olefinas internas a través de la migración.
Conclusiones:
- La adición catalizada por el paladio de triarilfosfinas y ácidos próticos a los alquenos es un método eficiente para sintetizar sales de 1-alquilofosfonio.
- La reacción exhibe buenos rendimientos y tolera varios sustratos de alquenos, incluidas las olefinas internas.
- Este sistema catalítico proporciona una valiosa nueva ruta para la síntesis de compuestos organofosforados.
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