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La hidrólisis anormal de las sales de 7-fosfanorbornenio: un caso de equivalencia fosfonio-fosfenio
Rongqiang Tian1, Hui Liu, Zheng Duan
1Chemistry Department, International Phosphorus Laboratory, Zhengzhou University, Zhengzhou 450052, PR China.
Journal of the American Chemical Society
|October 21, 2009
Resumen
La hidrólisis del triflato de fosfanorbornenio produce diferentes óxidos de fosfina en función de la base utilizada. La trietilamina conduce al óxido de fosfina terciario, mientras que la alfa-picolina da como resultado el óxido de fosfina secundario a través de la escisión del enlace P-C puente.
Área de la Ciencia:
- Química del organofosforo y su composición química.
- La síntesis orgánica es la síntesis orgánica.
- Mecanismos de reacción Los mecanismos de reacción.
Sus antecedentes:
- Los triflados de fosfanorborenio son compuestos organofosforados de tensión.
- La reactividad de estos compuestos en condiciones hidrolíticas no se comprende completamente.
- La comprensión de las vías de escisión de enlaces P-C es crucial para las aplicaciones sintéticas.
Objetivo del estudio:
- Para investigar los productos de hidrólisis de un triflato específico de fosfanorbornesio.
- Para determinar la influencia de diferentes bases aminas en la vía de la hidrólisis.
- Para dilucidar el mecanismo de la escisión de enlaces P-C en el sistema ciclico.
Principales métodos:
- Hidrólisis del triflato de fosfanorbornesio en presencia de trietilamina.
- Hidrólisis del triflato de fosfanorbornesio en presencia de alfa-picolina.
- Caracterización de los óxidos de fosfina resultantes mediante técnicas espectroscópicas.
Principales resultados:
- La hidrólisis con trietilamina rompió selectivamente un enlace P-C del puente, produciendo un óxido de fosfina terciario.
- La hidrólisis con alfa-picolina dio como resultado la escisión de ambos enlaces P-C del puente, proporcionando un óxido de fosfina secundario.
- La elección de la base dicta el grado de escisión de los enlaces P-C.
Conclusiones:
- La hidrólisis de los triflados de fosfanorbornesio es sensible a la nucleofilicidad y al impedimento estérico de la base amina.
- La escisión selectiva de enlaces P-C puede ser controlada por las condiciones de reacción.
- Este estudio proporciona información sobre la degradación controlada de los compuestos organofosforados estirados.
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