A DFT Study on the Reaction Mechanism Involved in the Synthesis of Sodium Azide via Hydrazine Hydrate Method

Sodium azide is a widely used inorganic compound. Besides the commonly used method of ＂Wislicenus process＂ which uses ammonia, nitrous and sodium as materials, the hydrazine hydrate route is also employed for the preparation of sodium azide particularly in laboratory. However, because many species are involved in the reaction system, the reaction details for the hydrazine hydrate route are still unclear. A comprehensive understanding of the reaction mechanism may provide meaningful help for optimizing the production process. In this work, the reaction mechanism for the synthesis of sodium azide by hydrazine hydrate route has been studied using density function theory（DFT） method. On the basis of our calculations, the reaction details, including the energetics of ten elementary steps, the structures of intermediates and transition states as well as the influence of inorganic acids and alcohols, were illuminated at the atomistic level. Both the two steps, the generation of key intermediate（NH2-NH-NO） and the trans-cistransformation of NH2-NH-NO, are suggested to be the possible rate-limiting step, corresponding to the energy barriers of 20.3 and 22.7 kcal/mol, respectively. In the early reaction steps to generate NH2-NH-NO, the main role of sulphuric acid is to donate proton, which can be replaced by nitric acid or hydrochloric acid. From the energy point of view, isopropanol has similar reactivity as methanol and ethanol.

Effects of Chemical Mutagen(Sodium Azide)on Onion Grown in Organic and Inorganic Fertilized Soil

The effects of chemical agent(Sodium Azide)on Onion growing in organic and inorganic fertile soil was to be examined during this study.The analy­sis work was carried out within the green house of the research laboratory technology of the Oke Ogun Science Laboratory Technology,Saki,Oyo State.Onion seeds were soaked inside different beakers containing the mixture of Sodium Azide and water mixed with 10 ml of Phosphate solu­tion for 4 hours.Also,the control was soaked with normal water and 10 ml of Phosphate buffer solution.The treated seeds of onions was planted in plastic containers containing 4.2 g of weighed humus soil within the green house at the Department of research lab Technology of The Oke Ogun poly­technic school,Saki Oyo State.The samples parameter were taken daily for six consecutive months.The result obtained was additionally subjected to statistical analysis by using DMRT techniques.The results showed that the stem length was ranged from 11.39±0.62 and 9.98±0.52 with sample of onion without sodium Azide and inorganic had the highest stem length values and samples of onion with Sodium Azide and inorganic had very cheap stem length.However,the leave length ranged from 29.63±0.12 and 22.45±0.10 with the Onion samples with inorganic and Organic fertilizers which had the highest leave length and sample of onion without Sodium Azide was very low leave length.The results of this study showed that each one the parameters studied within the plant were low with Sodium Azide treatment.The decrease in plant growth,plant heights,root lengths,and Phaonerogam survival,fruit yield per plant and height at maturity with agent concentration.It is hereof suggested that Sodium Azide(NaN3)was expected to produce mutation in onion that area unit extremely liable to harmful pathogens and making them cheap to be useful for farmers.

Synthesis and Structural Characterization of Bis(2,2'-bpy)bis(azide)cobalt(Ⅲ)nitrate dihydrate

The title complex [CoIII(2, 2?bpy)2(N3)2]種O3?H2O was obtained by an auto-oxidization reaction of cobalt nitrate with 2, 2-bpy and sodium azide in aqueous solution at room temperature, and violet single crystals were prepared in ethanol solution. The structure was determined by X-ray crystallography. The crystal is of triclinic, space group P ?with a = 8.285(4), b = 11.990(8), c = 12.596(7) ? a = 86.630(3), b = 86.280(5), g = 71.130(10)? C20H20CoN11O5, Mr = 553.40, Z = 2, V = 1180.6(12) ?, F(000) = 568, Dc = 1.557 g/cm3, m = 0.784 mm-1, R = 0.0403 and wR = 0.1008. The title complex consists of a [CoⅢ(2, 2?bpy)2(N3)2]+ cation, a NO3- anion and two lattice water molecules. The center CoⅢ ion coordinated by two chelating 2, 2?bpy ligands and two terminal azide groups with a CoN6 coordination environment exhibits a distorted octahedral geometry.

Effect of carrier and axial ligand on the photocatalytic activity of cobalt thioporphyrazine

The photocatalytic activity of cobalt octakis（butylthio） porphyrazine（CoPz（BuS）8） was assessed through photodegradation of the dye rhodamine B（RhB） in water under irradiation with a Xe lamp and aerated conditions.The photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 or SiO2@Fe3O4nanoparticles or coordinated with an axial azide ligand was also investigated.The results demonstrated that the photocatalytic activity of CoPz（BuS）8 loaded on Al2O3 was higher than that loaded on SiO2@Fe3O4.The kinetic curves of RhB degradation in aqueous solutions at different pH indicated the pseudo first-order kinetics of the reaction.The highest degradation rate for CoPz（BuS）8 loaded Al2O3 at pH = 4 after 160 min was 84.6%.However,the advantages of easier separation and recycling as well as the ability to terminate the reaction at any time for the CoPz（BuS）8 loaded SiO2@Fe3O4 cannot be ignored.When electron-rich NaN3 was coordinated with CoPz（BuS）8 as an axial ligand and loaded on Al2O3,the resulting catalyst produced more active oxygen species such as O2^- and HO· to promote the quicker degradation of RhB than that by the other catalysts.For the N3-coordinated CoPz（BuS）8 loaded on Al2O3,the reactions at pH = 4 and 7 distinctly deviated from first-order kinetics,and the degradation rate reached 77.6%after 80 min at pH = 4.

Rice Grain Chalkiness Is Negatively Correlated with Root Activity During Grain Filling

Field and pot experiments were conducted using indica rice varieties with differential chalkiness. There were significant differences in root activity among the varieties. The percentages of chalky grains and chalky area were both negatively correlated with root activity expressed as α-naphthylamine oxidation ability （RA） per gram of fresh root （RAfw） , RA per spikelet （RAgrn）, or RA per sink capacity （RAsink）. The RAsink was more closely related to chalkiness than RAt, and RAgrn when varieties differed greatly in panicle size and grain weight. Application of NO3^--N fertilizer at heading resulted in higher root activity and reduced chalkiness. Application of 30 mg/L NaN3 （respiration inhibitor） resulted in reduced root activity and increased chalkiness for one variety ＇GD9501＇, but for the other variety ＇Qinluai＇ was in reverse. The percentages of chalky grains and chalky area were negatively correlated with root activity at 10 days after heading under different chemical treatments （r=-0.8567^＊ and r=-0.9211^＊＊, respectively）.

Antimutagenic potential of curcumin on chromosomal aberrations in Allium cepa

Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells.

Tetrahydroxystilbene glucoside protects against sodium azide-induced mitochondrial dysfunction in human neuroblastoma cells

Objective:Mitochondrial dysfunction is evident in the early stage of Alzheimer's disease(AD).Therefore development of drugs that protect mitochondrial function is a promising strategy for AD.The present work was to investigate the effects of 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-glucosides(TSG) on a mitochondrial dysfunction cell model induced by sodium azide and elucidate the underlying mechanisms.Methods:Mitochondrial membrane potential(MMP) was detected by a fluorescence method.Cellular adenosine triphosphate(ATP) level was measured using a firefly luciferase-based kit.Reactive oxygen species(ROS) was detected using dichlorofluorescin diacetate(DCFH-DA).The expression levels of Bcl-2 and Bax were measured by Western blotting assay.Flow cytometry was utilized to measure apoptosis.Results:Pretreatment of TSG(25-200 μmol/L) for 24 h significantly elevated MMP and ATP content,reduced ROS level and Bax/Bcl-2 ratio,and inhibited apoptosis in SH-SY5 Y cells exposed to sodium azide.Conclusion:These results suggest that TSG protects SH-SY5 Y cells against sodium azide-induced mitochondrial dysfunction and apoptosis.These findings are helpful to understand the protective effect of TSG on mitochondria,which are involved in the early stage of AD.

Facile Synthesis of 4,5-Disubstituted 2H-1,2,3-Triazoles by Catalyst-free Cycloaddition between Substituted Vinyl Sul- fones and Sodium Azide under Ambient Conditionst

A highly efficient method for readily preparing 4,5-disubstituted 2H-1,2,3-triazoles was found. Under ambient conditions, a catalyst free cycloaddition between substituted vinyl sulfones and sodium azide could be completed in a very short time. In this cycloaddition process, sulfonyl group acts as a leaving group, while its ester group was retained.

Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometric Study on Sodium Azide Cluster Ions

Sodium azide has rarely been studied in gas phase or in the form of cluster ions and as a model of solid ener-getic substances and inorganic azide salt was ionized by electrospray ionization (ESI) and studied by high resolution Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) systematically. This paper highlights the effects of experimental conditions on the formation of salt cluster and the collision activation dissociation path-ways of cluster ions to develop a microscopic understanding of inorganic azide salt clusters.

Zinc chloride catalyzed synthesis of 5-substituted 1H-tetrazoles under solvent free condition

Zinc chloride is an efficient and safe catalyst in the [3 ＋ 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as： the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.

Bacterial Deterioration in the Limestone Minaret of Prince Muhammad and Suggested Treatment Methods, Akhmim, Egypt

El-Amir Muhammad’s minaret in Akhmim, Sohag, Egypt, is constructed of limestone and has been exposed to many factors of damage as a result of the high levels of ground water. Limestone is strongly affected by ground water, especially when being impure. The current work discusses the results of analytical techniques including chemical testing to determine the types of soluble salts through optical microscopy, electronic scanning electron microscope with an X-ray energy dispersion system (ESEM) to study and determine the causes of rapid degradation. Microbial weathering phenomena toward limestone were also studied. Different bacteria and fungi were isolated from outdoors and indoors of air and limestone of the building of which Bacillus cereus OK447647, B. subtilis OK447648, Serratia marcescens OK447650, Pseudomonasoryzihabitans OK447649, Aspergillus flavus, A. niger, Penicillium chrysogenum and Cladosporium cladosporoids were the most representative. B. cereus OK447647 and B. subtilis OK447648 have shown ability for calcium carbonate dissolving. The minimal inhibitory concentrations (MICs) of sodium azide were investigated against the growth of microbial isolates. Sodium azide at 100 ppm was found to be the best treatment for bacterial isolates although it had no significant effect against fungi.

One-pot,direct synthesis of acyl azides from carboxylic acids using Ph_2PCl/I_2/NaN_3 reagent system

A mild,efficient and simple method for the preparation of acyl azides from carboxylic acids using chlorodiphenylphosphine in the presence of molecular iodine and sodium azide is described.

Utilization of bromine azide to access vicinal-azidobromides from arylidene malononitrile

An efficient and facile approach for tetrachlorosilane as an in situ mediated transformation via a one-pot, synthesis of vicinal bromoazides through the generation of BrN3 from azidochlorosilane and N-bromosuccinimide in acetonitrile as solvent at ambient temperature is achieved. This catalytic process represents a highly regioselective and high yielding method for the synthesis of 1,2- bromoazides. Thiamine pyrophosphate （TPP） riboswitches regulate essential genes in bacteria by changing conformation upon binding intracellular TPP. Molecular docking studies are conducted to understand the orientation and the interaction of each synthesized molecules with TPP riboswitches, 2016 Chinese Chemical Society and Institute of Materia Medica, Chinese Academv of Medical Sciences.

One-Pot Synthesis of 4-Aryl-NH-1,2,3-Triazoles through Three- Component Reaction of Aldehydes, Nitroalkanes and NaN3

A one-pot three-component reaction of aldehydes, nitroalkanes and NaN3 for the synthesis ofNH-1,2,3-triazoles has been developed. The reaction provides a safe, efficient and step-economic approach for the synthesis of various NH-1,2,3-triazoles in good to excellent yields.