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De los complejos de tetrahidroborato a los complejos de aminoborilvinylideno-osmio a través de los intermediarios de
María L Buil1, Miguel A Esteruelas, Karin Garcés
1Departamento de Química Inorgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain. mbuil@unizar.es
Journal of the American Chemical Society
|January 29, 2011
Resumen
Los complejos de osmio con ligandos aminoborilo sufren transformaciones con alquinos y ácidos. Estas reacciones producen nuevos derivados de borilo y complejos de vinilideno, mostrando una nueva reactividad en la química organometálica.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- La catálisis de la catálisis.
Sus antecedentes:
- Los complejos de osmio son versátiles en las transformaciones sintéticas.
- Los ligandos del tetrahidroborato ofrecen vías de reactividad únicas.
- Los ligandos aminoborilo y alquinilo son grupos funcionales clave en la síntesis organometálica.
Objetivo del estudio:
- Para investigar la reactividad de los complejos de tetrahidroborato de osmio con aminas y alquinas.
- Para explorar la formación de nuevos derivados de aminoborilo y amino(fluoro) borilo osmio.
- Estudiar las transformaciones subsiguientes de estos complejos bajo diversas condiciones.
Principales métodos:
- Reacción del complejo tetrahidroborato de osmio (1) con las aminas primarias (anilina, p-toluidina).
- Tratamiento de los complejos de aminoborilo resultantes con fenilacetileno.
- Otras reacciones con ácido tetrafluorobórico (HBF(4)), ácido acético y monóxido de carbono (CO).
- Caracterización espectroscópica (NMR, difracción de rayos X) de los productos.
Principales resultados:
- Síntesis de complejos de aminoborilo ósmio (2, 3) a partir del complejo 1 y aminas.
- Formación de complejos de alquinyl-aminoboryl osmium (4, 5) a través de la reacción con el fenilacetileno.
- Conversión a las especies amino (fluoro) borilo (6, 7) utilizando HBF (4).
- Generación de complejos de seis coordenadas (8-11) mediante la adición de ácido acético o CO.
- Observación de la migración de 1,3-borilo que conduce a los aminoborilvinilidos (12, 13) y derivados del fluoro relacionados (17, 18).
Conclusiones:
- Los complejos de tetrahidroborato de osmio exhiben una rica reactividad hacia aminas y alquinas.
- Se puede lograr una funcionalización diversa de los complejos de osmio, lo que lleva a los derivados de aminoborilo, amino ((fluoro)) borilo y vinylideno.
- El estudio destaca nuevas vías de inserción y reordenamiento migratorio en la química del osmio.
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