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Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
Preparación y propiedades de un complejo monomérico Mn(IV) -oxo
Trenton H Parsell1, Rachel K Behan, Michael T Green
1Department of Chemistry, University of Kansas, 2010 Malott Hall, 1251 Wescoe Hall Drive, Lawrence, Kansas 66045, USA.
Journal of the American Chemical Society
|July 6, 2006
Resumen
Este estudio detalla la síntesis y caracterización de un nuevo complejo mononuclear manganeso-oxo, específicamente una unidad de oxomanganeso (IV). La investigación pone de relieve sus propiedades espectroscópicas únicas y su diversa reactividad, avanzando en la investigación de la catálisis.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Química organometálica Química orgánica de los metales.
- Investigación de la investigación de la catálisis.
Sus antecedentes:
- Los complejos manganeso-oxo son cruciales en la catálisis biológica y química.
- Los complejos monoméricos con ligandos oxo terminales, especialmente el oxomanganeso (IV), son raros.
- Los trabajos anteriores se centraron en los complejos de Mn{III}-O, siendo la escisión del oxígeno un paso clave.
Objetivo del estudio:
- Sintetizar y caracterizar un nuevo complejo mononuclear de oxomanganeso (IV).
- Investigar las propiedades espectroscópicas y estructurales del complejo sintetizado.
- Para explorar la reactividad de la unidad de oxomanganeso (IV) en varias transformaciones químicas.
Principales métodos:
- Síntesis del complejo de oxomanganeso (IV) [MnIVH3buea (O) ]- a partir de un precursor de Mn (III) -O.
- Caracterización mediante espectroscopia UV-Vis, espectroscopia Raman de resonancia y resonancia paramagnética de electrones (EPR).
- Análisis computacional utilizando la Teoría Funcional de Densidad (DFT) para apoyar las asignaciones estructurales.
Principales resultados:
- Preparación y caracterización exitosas de un complejo mononuclear Mn(IV) -oxo con S = 3/2 estado fundamental.
- Los datos espectroscópicos (lambdamax = 635 nm, nu(Mn-O) = 737 cm-1) y EPR (g = 5.15, 2.44, 1.63) confirman la asignación de Mn(IV) -oxo.
- Los cálculos de DFT apoyan la asignación e indican la distorsión de Jahn-Teller, que se desvía de la simetría trigonal.
- El complejo exhibe una reactividad diversa, incluida la transferencia de átomos O a fosfinas y la reacción con hidrazina, pero es inestable en DMSO.
Conclusiones:
- Se ha sintetizado y caracterizado completamente un complejo de oxomanganeso mononuclear estable (IV).
- El complejo muestra patrones de reactividad únicos, que muestran el potencial de las unidades de Mn (IV) -oxo en la catálisis.
- Este trabajo amplía los ejemplos conocidos de complejos mononucleares Mn(IV) -oxo y su comportamiento químico.
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