Video Experimental Relacionado
Updated: Jul 15, 2026
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Estructura molecular y conformación del dinitrosilhemo
Jeanet Conradie1, Tebikie Wondimagegn, Abhik Ghosh
1Department of Chemistry, Faculty of Science, University of Tromsø, N-9037 Tromsø, Norway.
Journal of the American Chemical Society
|April 24, 2003
Resumen
Dinitrosylheme, una especie reactiva, muestra una fuerte preferencia por una conformación cis, contrariamente a las sugerencias anteriores. Los cálculos de la Teoría Funcional de Densidad (DFT, por sus siglas en inglés) revelan esta preferencia de orientación única, importante por su relevancia biológica.
Área de la Ciencia:
- Química computacional es la química computacional.
- Química bioorgánica Química bioorgánica.
Sus antecedentes:
- Dinitrosylheme es una especie reactiva única con potencial relevancia biológica.
- Se han reportado recientes generaciones de baja temperatura y caracterización espectroscópica.
- Los datos espectroscópicos IR anteriores sugirieron una conformación transcentrosimétrica.
Objetivo del estudio:
- Para investigar la orientación preferida del ligando en dinitrosilhemas utilizando métodos computacionales.
- Para resolver las discrepancias entre las predicciones teóricas y los datos espectroscópicos existentes.
Principales métodos:
- Se emplearon cálculos de la Teoría Funcional de Densidad (DFT).
- Se evaluó la favorabilidad energética de las conformaciones cis y trans.
Principales resultados:
- Los cálculos de DFT favorecen fuertemente una conformación cis C2v para los dos ligandos NO.
- La conformación cis es energéticamente preferida sobre la orientación trans por aproximadamente 20 kcal/mol.
- Este hallazgo contrasta con la transconformación propuesta anteriormente por la espectroscopia de infrarrojos.
Conclusiones:
- El estudio indica una preferencia significativa de orientación cis para los ligandos de NO en el dinitrosilhemo.
- Los resultados computacionales desafían las interpretaciones anteriores de los datos espectroscópicos.
- Comprender esta conformación es crucial para aclarar la relevancia biológica del dinitrosilhemo.
Videos de Conceptos Relacionados
02:34Structural Isomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
01:16Structure of Conjugated Dienes
Introduction
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the double...
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the double...
01:28Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.
01:07Structure of Benzene: Kekulé Model
In 1865, August Kekule suggested the structure of benzene according to the structural theory of organic chemistry based on the three assertions—formula of benzene is C6H6, all the hydrogens of benzene are equivalent, and each carbon must have four bonds due to its tetravalency.
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
01:19Structure of Amines
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are illustrated in Figure...
01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...