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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Amoniaco triborano: una nueva síntesis, determinaciones estructurales y propiedades hidrolíticas de liberación de
Chang Won Yoon1, Patrick J Carroll, Larry G Sneddon
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
Journal of the American Chemical Society
|December 17, 2008
Resumen
El triborano de amoníaco (NH 3 B 3 H 7) puede prepararse con seguridad y exhibe una estructura asimétrica en estado sólido debido a la unión de dihidrógeno. Sus soluciones acuosas liberan rápidamente hidrógeno con un catalizador de metales de transición.
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 boranos son una clase de compuestos de boro-hidrógeno con aplicaciones potenciales en el almacenamiento de hidrógeno.
- La síntesis y caracterización del triborano de amoníaco (NH 3 B 3 H 7) son cruciales para explorar sus propiedades.
- Comprender los aspectos estructurales y de reactividad del triborano de amoníaco es clave para su utilización práctica.
Objetivo del estudio:
- Desarrollar un método seguro y conveniente para la preparación de triborano de amoníaco (NH 3 B 3 H 7)
- Para investigar la estructura en estado sólido del triborano de amoníaco y sus aductos utilizando cristalografía de rayos X y cálculos DFT.
- Para estudiar las características de liberación de hidrógeno de las soluciones acuosas de amoníaco triborano.
Principales métodos:
- Síntesis de triborano de amoníaco a través de la oxidación con yodo de B ((3) H ((8)) seguido por el desplazamiento de amoníaco.
- Cristalografía de rayos X para determinar la estructura en estado sólido de NH ((3) B ((3) H ((7)) y su adducto de 18 coronas-6.
- Computaciones de la Teoría Funcional de Densidad (DFT) para analizar la estructura molecular y los enlaces.
- Estudios de reacción hidrolítica con catalizadores ácidos o de metales de transición (Rh/Al2O3) para medir la liberación de hidrógeno.
Principales resultados:
- Se estableció una preparación segura y conveniente de triborano de amoníaco (NH 3 B 3 H 7)
- Los estudios de cristalografía de rayos X y DFT revelaron una estructura de estado sólido altamente asimétrica de NH(3)B(3)H(7) impulsada por enlaces de dihidrógeno intermoleculares N-H(+)...H(-) -B, contrariamente a las predicciones computacionales de simetría.
- Las soluciones acuosas de triborano de amoníaco liberan rápidamente hidrógeno con la adición de ácido o un catalizador Rh/Al, logrando una liberación de 6,1 wt% de H2, bajo condiciones específicas.
Conclusiones:
- El triborano de amoníaco (NH 3 B 3 H 7) puede sintetizarse eficazmente utilizando un nuevo método.
- La estructura en estado sólido del triborano de amoníaco está significativamente influenciada por la unión de dihidrógeno intermolecular, lo que lleva a la asimetría.
- El triborano de amoníaco es un material de almacenamiento de hidrógeno prometedor, con tasas de liberación de hidrógeno controlables facilitadas por catalizadores.
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