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Reacciones de los amidinatos de boro con CO2 y CO y otras moléculas pequeñas
Meghan A Dureen1, Douglas W Stephan
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6.
Journal of the American Chemical Society
|September 3, 2010
Resumen
El borano de Piers reacciona con las carbodiimidas para formar amidinatos de boro. Estos compuestos se someten a diversas reacciones de inserción con sustratos como CO2, CO y nitriles, mostrando su reactividad.
Área de la Ciencia:
- Química del organoborón Química del organoborón
- Grupo Principal Química.
- Química orgánica sintética y orgánica.
Sus antecedentes:
- Los amidinatos de boro son una clase de compuestos con aplicaciones potenciales en catálisis y ciencias de los materiales.
- Comprender la reactividad de los amidinatos de boro es crucial para desarrollar nuevas metodologías sintéticas.
- El borano de Piers, HB ((C6F5) 2), es un reactivo bien establecido en la química del organoboron.
Objetivo del estudio:
- Para investigar la reacción del borano de Piers con las carbodiimidas.
- Para explorar la química de la reacción de inserción de los amidinatos de boro resultantes.
- Para aclarar las propiedades estructurales y reactivas de estos nuevos compuestos de boro.
Principales métodos:
- Síntesis de amidinatos de boro a través de la reacción del borano de Piers con el tert-butilo o el isopropilo carbodiimida.
- Caracterización de productos mediante el uso de técnicas espectroscópicas (NMR, etc.). En el caso de las personas que se encuentran en situación de exclusión social.
- Investigación de la reactividad a través de varias reacciones de inserción con sustratos como CO2, CO, nitriles y aldehídos.
Principales resultados:
- Los amidinatos de boro HC(RN) 2B(C6F5) 2 [R = iPr (1), tBu (2) ] fueron sintetizados con éxito.
- Los compuestos 1 y 2 exhibieron diversas reacciones de inserción con CO2, CO, CNtBu, benzaldehído y MeCN.
- La termólisis del compuesto 1 produjo un producto que sugiere la participación de una forma transitoria de "cadena abierta".
Conclusiones:
- Los amidinatos de boro sintetizados son sintones versátiles capaces de someterse a una serie de reacciones de inserción.
- La reactividad observada apoya la existencia transitoria de una forma de "cadena abierta" en solución.
- Este estudio amplía la reactividad conocida de los compuestos organoboron y proporciona información sobre sus mecanismos de reacción.
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