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Viaje de los bonos cuádruples Mo-Mo a los bonos quíntuple
Yi-Chou Tsai1, Hong-Zhang Chen, Chie-Chieh Chang
1Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan, ROC. yictsai@mx.nthu.edu.tw
Journal of the American Chemical Society
|August 19, 2009
Resumen
Los investigadores sintetizaron nuevos complejos de dimolibdeno con enlaces cuádruples y quíntuplos. Estos complejos exhiben los enlaces metal-metal más cortos observados hasta ahora más allá de la primera fila de elementos, confirmados por los cálculos de DFT.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Ciencia de los materiales Ciencia de los materiales.
- Química computacional es la química computacional.
Sus antecedentes:
- Los complejos de dimolibdeno son conocidos por exhibir múltiples enlaces metal-metal.
- Las estructuras de ruedas de remolque son comunes en la química del dimolibdeno.
- La exploración de enlaces metal-metal de orden superior es crucial para comprender el enlace químico.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos complejos de dimolibdeno con enlaces cuádruples y quintuples.
- Investigar las propiedades estructurales y electrónicas de estos nuevos complejos.
- Para explorar la formación de los enlaces metal-metal más cortos más allá de los elementos de la primera fila.
Principales métodos:
- Síntesis de complejos de dimolibdeno a través de la reacción de K ((4) Mo ((2) Cl ((8)) con los ligandos Li [RC (((NDipp) ((2) ].
- Caracterización estructural mediante cristalografía de rayos X.
- Análisis de la estructura electrónica utilizando cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- Se sintetizaron dos complejos de dimolibdeno cuádruplamente unidos de tipo paddlewheel, Mo(2)(mu-Cl)[Cl(2)Li(OEt(2))][mu-eta(2)-RC(N-2,6-i-Pr(2)C(6)H(3))(2)](2), en los que se encuentran los siguientes compuestos:
- La reducción de estos complejos produjo complejos de enlace quíntuple Mo-Mo, Mo ((2) [mu-eta ((2) -RC ((N-2,6-i-Pr ((2) C ((6) H ((3)) ((2)))), con longitudes de enlace Mo-Mo significativamente más cortas.
- Las longitudes de enlace Mo-Mo resultantes representan los enlaces metal-metal más cortos observados más allá de los elementos de la primera fila.
Conclusiones:
- La síntesis exitosa de complejos de dimolibdeno con enlaces cuádruples y quintuples amplía el alcance de los enlaces múltiples en la química inorgánica.
- Los enlaces metal-metal más cortos observados proporcionan información sobre la naturaleza del enlace en los metales pesados de transición.
- Los cálculos de DFT corroboran la presencia de la unión quíntuple y las características estructurales de los complejos sintetizados.
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