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DFT method (B3LYP) with 6-31G* basis set was utilized in the computation of a fully optimized structure, net atomic charges and spin densities of the intermediate of cytochrome P-450-oxoiron(IV) porphyrin cation radical, compound I – in the presence of axial ligand such as thiolate (SMe−) imidazole (IM), phenoxide (OPh−), methoxide (OMe−) and chloride (Cl−). The results show doublet states in compound I are about 2–4 kcal/mol more stable than quartet states for all aforementioned ligands, and the doublet state is the ground state in all cases. However, electron donor ability of the ligands are in the order of SMe− > IM > OMe− > OPh− > Cl−. Also the active oxidant intermediate of cytochrome P-450 between different mesomeric structures select sulfur oxygen radical type structure and can be viewed as (RS↓)Fe↑(IV)(O↑)(Por). In horseraddish peroxidase (HRP) and peroxidase with histidine axial ligand π cation radical character of porphyrin ring is preferred (Im)Fe↑(IV)(O↑)(Por↓). For the ligands such as OMe−, OPh− and Cl− oxidation mainly took place on the iron and the active intermediate can be viewed as (L)Fe↑(V)(O)(Por) with one unpaired electron localized on the iron. 相似文献
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Dr. Mahnaz Najafi Dr. Sara Abednatanzi Abbas Yousefi Prof. Mehrorang Ghaedi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(72):17999-18014
Photocatalysis has been known as one of the promising technologies due to its eco-friendly nature. However, the potential application of many photocatalysts is limited owing to their large bandgaps and inefficient use of the solar spectrum. One strategy to overcome this problem is to combine the advantages of heteroatom-containing supports with active metal centers to accurately adjust the structural parameters. Metal nanoparticles (MNPs) and single atom catalysts (SACs) are excellent candidates due to their distinctive coordination environment which enhances photocatalytic activity. Metal-organic frameworks (MOFs), covalent organic frameworks (COFs) and carbon nitride (g-C3N4) have shown great potential as catalyst support for SACs and MNPs. The numerous combinations of organic linkers with various heteroatoms and metal ions provide unique structural characteristics to achieve advanced materials. This review describes the recent advancement of the modified MOFs, COFs and g-C3N4 with SACs and NPs for enhanced photocatalytic applications with emphasis on environmental remediation. 相似文献
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Reza Ghiasi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(13):2231-2238
The density functional theory (DFT) is used to study the geometries, and electronic structures of triplet and singlet of borazyne and B-substituted of borazyne. The aromaticity of these systems is analyzed in the light of nucleus-independent chemical shift (NICS), average of two-center indices (ATI). These methods show increasing of aromaticity in deactivating groups. The relation between electron density in ring critical point (RCP) and NICS(1.0) is observed. The most important interaction in these molecules has been investigated by natural bonding orbital method (NBO). 相似文献
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Sarvin Hossien Saraf Reza Ghiasi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(5):1047-1052
Russian Journal of Physical Chemistry A - In this study, using the B3LYP* method, quantum chemical computations were applied for analyzing the effects of solvent on the electronic spectrum features... 相似文献
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Afradi Nahid Foroughifar Naser Pasdar Hoda Qomi Mahnaz 《Research on Chemical Intermediates》2019,45(5):3251-3271
Research on Chemical Intermediates - Mn0.5Fe0.25Ca0.25Fe2O4@starch@aspartic acid magnetic nanoparticles (MNPs) as a new green nanocatalyst were designed and synthesized by a coprecipitation... 相似文献
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Mohammad Edrissi Meysam Soleymani Mahnaz Naderi 《Journal of Sol-Gel Science and Technology》2012,64(2):485-492
Nanocrystalline manganese aluminate (MnAl2O4) has been synthesized by Pechini and sequential homogenous precipitation methods and the results have been compared. The Taguchi L4 statistical design was utilized to optimize the production of MnAl2O4 nanoparticles by Pechini method. The MnAl2O4 nanocrystallites obtained by Pechini and sequential homogenous precipitation methods had the average particle size of 26.5 and 49.5 nm, respectively. The products were characterized with X-ray diffraction, laser light scattering, thermogravimetry analysis, Fourier transform infrared, UV–visible, energy dispersive X-ray, scanning electron microscope and inductively coupled plasma analyses. The photocatalytic activities of MnAl2O4 nanoparticles synthesized by two methods were investigated using aqueous solution of methylene blue under irradiation of visible light. 相似文献
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A simple and efficient procedure has been developed for the synthesis of biologically relevant 2‐substituted benzimidazoles through a one‐pot condensation of o‐phenylenediamines with aryl aldehydes catalysed by iron oxide magnetic nanoparticles (Fe3O4 MNPs) in short reaction times with excellent yields. In the present study, Fe3O4 MNPs synthesized in a green manner using aqueous extract of white tea (Camelia sinensis) (Wt‐Fe3O4 MNPs) were applied as a magnetically separable heterogeneous nanocatalyst to synthesize 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole which has potential application in pharmacology and biological systems. Fourier transform infrared and NMR spectroscopies were used to characterize the 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole. In vitro cytotoxicity studies on MOLT‐4 cells showed a dose‐dependent toxicity with non‐toxic effect of 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole, up to a concentration of 0.147 µM. The green synthesized Wt‐Fe3O4 MNPs as recyclable nanocatalyst could be used for further research on the synthesis of therapeutic materials, particularly in nanomedicine, to assist in the treatment of cancer. 相似文献
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Farahnaz Nourmohammadian Mahnaz Davoudzadeh Gholami 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):340-346
A convenient and efficient, regioselective, solvent-free procedure has been developed to react 2,6-dihydroxyanthraquinone, dialkyl acetylenedicarboxylates, and triphenylphosphine in one-pot, to afford novel phosphanylidene anthracenyl derivatives 3a-c, which at 90°C due to intramolecular nucleophilic attack formed novel phosphanylidene anthra[2,1-b]furans 4a–c in good yield. 相似文献