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Eliminación reductora de carbono-carbono de los alquilos homolepticos de uranio (IV) inducidos por ligandos
Steven J Kraft1, Phillip E Fanwick, Suzanne C Bart
1H.C. Brown Laboratory, Department of Chemistry, Purdue University, West Lafayette, Indiana 47906, USA.
Journal of the American Chemical Society
|April 4, 2012
Resumen
Este estudio informa sobre la síntesis y caracterización de los alquilos de uranio (IV) Estos compuestos se someten a una eliminación reductiva con ligandos alfa-diimine, pero son estabilizados por ligandos de fosfina, lo que impide esta reacción.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química del Uranio La Química del Uranio
- Coordinación Química de la Coordinación
Sus antecedentes:
- Los alquilos homoleptos del uranio (IV) son importantes para comprender la reactividad del uranio.
- La síntesis y caracterización de nuevos complejos de uranio proporcionan información sobre la química del elemento f.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos complejos alquilo homolepticos de uranio (IV).
- Para investigar la reactividad de estos complejos con ligandos redox-activos y redox-inocentes.
- Para dilucidar los mecanismos de eliminación reductora y estabilización en compuestos organometálicos de uranio.
Principales métodos:
- Síntesis de alquilos de uranio (IV) mediante la reacción de UCl (IV) con benzilos de potasio.
- Caracterización mediante cristalografía de rayos X, estudios magnéticos, (1) espectroscopia de RMN H y GC/MS.
- Estudios de reactividad que involucran la adición de alfa-diimina y ligandos de fosfina.
Principales resultados:
- Se han sintetizado y caracterizado con éxito los complejos de U (Ar = Ph, p-CH) (C) (H) (4), m-CH) (C) (H) (C) (H) (C) (H) (C) (H)) (Ar = Ph, p-CH) (C) (C) (H) (C) (H)) (C) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H)) (H) (H) (H) (H) (H) (H)) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H)) (H) (H) (H) (H)) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H) (H)
- Se ha confirmado la coordinación eta(4) de los ligandos benzilos y una configuración electrónica U(IV) 5f(2).
- Se observó la eliminación reductiva del bibencilo tras la adición de un ligando alfa-diimine, pero la estabilización por un ligando fosfina.
Conclusiones:
- Los alquilos homoleptos de uranio (IV) pueden ser sintetizados y caracterizados.
- La reactividad de estos complejos depende de la naturaleza del ligando auxiliar.
- Los ligandos alfa-diimina promueven la eliminación reductora, mientras que los ligandos fosfina estabilizan el centro del uranio.
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