Un carbino terminal de cobalto altamente reducido: Reactividad divergente centrada en metales y α-carbono
Charles C Mokhtarzadeh1, Curtis E Moore1, Arnold L Rheingold1
1Department of Chemistry and Biochemistry , University of California, San Diego , 9500 Gilman Drive, Mail Code 0358 , La Jolla , California 92093-0358 , United States.
Journal of the American Chemical Society
|June 16, 2018
Resumen
Los investigadores aislaron un complejo de carbino de cobalto único. Este centro de cobalto de baja valencia actúa como un nucleófilo y sufre reacciones de cicloadición, formando nuevos enlaces carbono-carbono.
Área de la Ciencia:
- Química organometálica
- Química de coordinación
Sus antecedentes:
- Las carbinas terminales son intermedios reactivos en la química organometálica.
- Los centros metálicos de baja valencia con ligandos ricos en electrones pueden exhibir una reactividad única.
Objetivo del estudio:
- Aislar y caracterizar un nuevo carbino terminal de cobalto dianiónico.
- Investigar las propiedades electrónicas y la reactividad de este complejo de carbino de cobalto.
Principales métodos:
- Reducción química de un precursor de ligando de isocyanuro.
- Cristalografía de rayos X para la determinación estructural.
- Análisis espectroscópicos (por ejemplo, RMN, IR) y computacionales para la caracterización electrónica.
Principales resultados:
- Aislamiento de un complejo de carbino terminal de cobalto dianiónico.
- Los datos cristalográficos y espectroscópicos indican un centro de cobalto de baja valencia con una variedad d-orbital llena.
- El centro de cobalto exhibe un carácter nucleófilo hacia sustratos protóticos y electrofilos silílicos.
- El carbono carbino participa en reacciones de cicloadición [2+2] con alquinas internas, formando nuevos enlaces C-C.
Conclusiones:
- La estructura electrónica del carbino de cobalto dicta su doble reactividad como nucleófilo y participante en la cicloadición.
- Este estudio amplía la reactividad conocida de los complejos de cobalto de baja valencia y las carbinas terminales.
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