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Activación de un complejo abierto de diironio con puente de carbino para la unión de nitrógeno
Charles H Arnett1, Theodor Agapie1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|April 15, 2020
Resumen
Los investigadores han modelado la nitrogenasa
Área de la Ciencia:
- Química bioorgánica
- Química organometálica
- Catálisis
Sus antecedentes:
- La activación del cofactor FeMo de la nitrogenasa para la unión con N2 es poco conocida.
- La cristalografía sugiere que la reducción de N2 ocurre en un sitio de diironio con puente de carbono.
Objetivo del estudio:
- Modelación de la activación de un sitio Fe-C para la unión de N2.
- Sintetizar y caracterizar un nuevo ligando de hexafosfina dinucleante y su complejo de diirón μ-carbina.
Principales métodos:
- Síntesis de un ligando de hexafosfina y su complejo de diirón μ-carbina.
- Caracterización mediante magnetometría SQUID, espectroscopia Mössbauer y cálculos DFT.
- Estudios mecánicos relacionados con la unión de H+, e- y N2.
Principales resultados:
- Se sintetizó un complejo único de diiron μ-carbyne (P6ArC) Fe2 ((μ-H) con un estado básico de S = 1.
- Este complejo se activa hacia la unión de N2 con la adición de fuentes de H+/e-.
- Se identificó un intermediario de hierro-carbeno capaz de coordinar el N2.
Conclusiones:
- El estudio proporciona un modelo para la activación reductora del cofactor FeMo en la nitrogenasa.
- Se caracterizó un nuevo motivo Fe (μ-carbina) (μ-H) Fe.
- Se obtuvieron conocimientos sobre el mecanismo de unión y reducción de N2 en los centros de hierro.
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