Hydrazine Research Articles

Photothermally-activated suspended aerogel triggers a biphasic interface reaction for high-efficiency and additive-free hydrogen generation.

The need for a sustainable hydrogen supply has sparked significant efforts to develop effective liquid hydrogen carriers with high hydrogen content that can be safely stored and undergo controlled hydrogen release. However, a major challenge lies in the ultralow hydrogen evolution rate caused by the direct dehydrogenation of liquid hydrogen carriers. Conventionally, accelerant additives are employed to improve the dehydrogenation rate, but this strategy inevitably sacrifices the hydrogen storage density. Therefore, achieving high-efficiency hydrogen release and high storage density remains a daunting task. Herein, we develop an innovative photothermally-activated suspended biphasic reaction strategy, which absorbs solar radiation and re-radiates infrared photons to induce photothermal evaporation and in situ dehydrogenation of liquid hydrogen carriers, fundamentally circumventing the employment of additives. Furthermore, by leveraging this phase transition-induced biphasic reaction design, the strategy improves the required reaction temperature and drastically lowers hydrogen transport resistance. Therefore, an impressive hydrogen evolution rate of 386 mmol g-1 h-1 is achieved from pure formic acid with an ultrahigh hydrogen storage density of 53 g L-1, representing a threefold improvement in rate compared to state-of-the-art strategies. Our approach introduces a fresh perspective for the dehydrogenation of liquid hydrogen carriers, encompassing formic acid, hydrazine hydrate, and so on, and concurrently guarantees exceptional hydrogen release capabilities and excellent hydrogen storage density.

Green synthesis of nitrogen-doped TiO2 nanoparticles with exposed {001} facets using Chromolaena odorata leaf extract for photodegradation of pollutants under visible light

Facet-tailored TiO2 nanoparticles (NPs) exhibit exceptional properties due to high surface energy. Conventional strategies for the fabrication of such TiO2 NPs involve harmful chemicals, which necessitates the development of environmentally benign pathways. Plant extract-assisted synthesis has emerged as a promising green alternative to conventional nanomaterial synthesis. This work introduces an innovative method for the synthesis of nitrogen-doped TiO2 (N-TiO2) NPs with exposed {001} facets using the leaf extract of a weed plant Chromolaena odorata, which is commonly known as Siam weed. The synthesis was carried out by sol-gel process with triethylamine (TEA), hydrazine hydrate and urea being the nitrogen precursors. The synthesised N-TiO2 NPs exhibited exposed {001} facets and showed a reduction in band gap. Photo-induced degradation of methylene blue dye was used to analyse the photocatalytic capability of N-TiO2 NPs in the visible range. The effect of N precursor, N dosage and light exposure time on the catalytic efficacy was studied. N-TiO2 NPs derived from TEA with 1 mol.% dopant achieved 98 % degradation in 180 minutes, while those synthesized with hydrazine and urea attained 96 % and 93 %, respectively when compared to 90 % degradation for undoped samples. The N-doping leads to significant advancement of photocatalytic effectiveness of the TiO2 NPs by introducing mid-gap levels in the forbidden energy gap that diminishes the charge carrier-recombination and boost the charge-carrier mobility of TiO2. This along with the existence of high energy facets causes a substantial advancement in the photocatalytic function in the visible region. The proposed method is a sustainable way for synthesising N-TiO2 NPs with exposed {001} facets for environment remediation applications.

Computational Studies and Antimicrobial Activity of 1-(benzo[d]oxazol-2- yl)-3,5-diphenylformazan Derivatives.

Due to the biological importance of the benzoxazole derivatives, some 1- (benzo[d]oxazol-2-yl)-3,5-diphenyl-formazans 4a-f were synthesized and screened for in-silico studies and in-vitro antibacterial activity. The benzo[d]oxazole-2-thiol (1) was prepared by reacting with 2-aminophenol and carbon disulfide in the presence of alcoholic potassium hydroxide. Then 2-hydrazinylbenzo[d] oxazole (2) was synthesized from the reaction of compound 1 with hydrazine hydrate in the presence of alcohol. Compound 2 was reacted with aromatic aldehydes to give Schiff base, 2-(2- benzylidene-hydrazinyl)benzo[d]oxazole derivatives 3a-f. The title compounds, formazan derivatives 4a-f, were prepared by a reaction of benzene diazonium chloride. All compounds were confirmed by their physical data, FTIR, 1H-NMR, and 13CNMR spectral data. All the prepared title compounds were screened for in-silico studies and in-vitro antibacterial activity on various microbial strains. Molecular docking against the 4URO receptor demonstrated that molecule 4c showed a maximum dock score of (-) 8.0 kcal/mol. MD simulation data reflected the stable ligand-receptor interaction. As per MM/PBSA analysis, the maximum free binding energy of (-) 58.831 kJ/mol was exhibited by 4c. DFT calculation data confirmed that most of the molecules were soft molecules with electrophilic nature. The synthesized molecules were validated using molecular docking, MD simulation, MMPBSA analysis, and DFT calculation. Among all the molecules, 4c showed maximum activity. The activity profile of the synthesized molecules against tested micro-organisms was found to be 4c>4b>4a>4e>4f>4d.

A silica gel-supported schiff base palladium nanocatalyst for sonogashira cross-coupling and synthesis of an anti-cancer chemotherapeutic agent

This work outlines the synthesis of a low-cost reusable silica gel-supported Schiff-base palladium nanocatalyst and its application in the synthesis of anti-cancer agent Eniuracil via the Sonogashira reaction. Silica gel was functionalized with amino containing silyl followed by the generation of a Schiff base through reaction with 1,10-phenanthroline-2,9-dicarboxaldehyde. Palladium was then coupled in the presence of hydrazine hydrate, resulting in the formation of the silica gel-supported Schiff-base palladium nanocatalyst (Si@SBPdNPs 3). Successful palladium incorporation was confirmed through Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses. Scanning Electron Microscope (SEM) images revealed spherical silica gel particles and Transmission Electron Microscopy (TEM) analysis indicated an average palladium nanoparticle size of 5.92 ± 0.1 nm. The Inductively Coupled Plasma (ICP) and Energy Dispersive X-ray (EDX) data confirmed the anchoring of 0.27 mol% of palladium to the Schiff-base in the catalyst. The industrial efficacy of the catalysts is demonstrated through its application in carbon-to-carbon bond formation between aryl halides and aromatic alkyne via the Sonogashira reaction. Furthermore, the catalyst proved effective in the synthesis of the anti-cancer agent Eniuracil, a vital component in fluoropyrimidine-based chemotherapy. The catalyst exhibited reusability without significant loss of productivity, demonstrating its robustness in C C bond formation in organic synthesis.

A new difunctional nanopolypropylene surface molecularly imprinted polyacrylamide catalytic probe for determination of trace sulfadiazine with resonance Rayleigh scattering technique

A new nanopolypropylene (PP) surface molecularly imprinted polyacrylamide (PP@MIP) probe was synthesized facilely for the Resonance Rayleigh Scattering (RRS) determination of trace sulfadiazine (SDZ), using PP as nanosubstrate, SDZ as template molecule, and the acrylamide as functional monomer. The catalytic effect of PP@MIP on the reduction of HAuCl4 by hydrazine hydrate to form AuNP, a nano-indicated reaction, was investigated. The generated AuNPs had a strong RRS effect, and the addition of SDZ resulted in the selective formation of PP@MIP-SDZ complex, which further promoted the generation of AuNP and increased the RRS signal. Therefore, there was developed a novel RRS assay platform for rapid, selective and sensitive detection of SDZ with a linearity range of 0.0125–0.150 nmol/L and limit of detection of 0.004 nmol/L. The recoveries were in the range of 93.3–109.9 % with the relative standard deviations (RSDs) in the range of 2.55–9.14 % in the real sample analysis.

Ultrasonic Mediated Synthesis of Dihydropyrano [2, 3-C] Pyrazole Derivatives Catalyzed By Cyanuric Acid/1-Methyl Imidazole

A Novel approach for the synthesis of dihydropyrano[2,3-c] pyrazoles via four-component reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehydes and malononitrile at room temperature under ultrasound irradiation is described. The reaction has been catalyzed by cyanuric acid and 1-methyl inidazole in aqueous medium. This protocol afforded several advantages such as easily available catalyst, simple operational procedure, excellent yield and ultrasound irradiation.

New mercaptopyrimidine derivatives synthesized with expected antimicrobial and antioxidant properties and theoretical study

In this elucidation, we synthesized different heterocyclic containing the thiopyrimidine nuclei, through the esterification of 2-mercapto pyrimidine with ethyl chloroacetate to give the corresponding ethyl 2-(pyrimidine-2-ylthio)acetate. Treatment of the ester compound 3 with hydrazine hydrate gave 2-(pyrimidin-2-ylthio)acetohydrazide 4 which acts as the building block for the synthesis of different heterocycles. Firstly the reaction with phenylisothiocyanate to afford the hydrazinecarbothioamide derivative 6 which cyclized in the presence of acidic and basic medium to give ((pyrimidin-2-ylthio)methyl)-1,3,4-thiadiazol-2-amine and triazole derivatives 7,8; respectively. Additionally, the formation of 2-((hydrazinylmethylthio)pyrimidine10 which is reacted with galactose ring to give methyl)hydrazinyl)hept‑6-ene-1,2,3,4,5-pentayl pentaacetate derivative 13 in the presence of acetic acid. All the synthesized compounds were investigated through spectral analysis of 1HNMR, 13CNMR, FT-IR, and mass spectrum. Moreover, the antimicrobial activity of the samples was examined in vitro on both gram-positive and gram-negative bacteria and fungi. Compound 13 displayed a strong efficiency against Bacillus cereus, Staphylococcus aureus, and Pseudomonas aeruginosa, All tested heterocycles exhibited remarkable inhibitory effects against the other pathogenic organisms. Antifungal screening of synthesized heterocycles varied and ranged from no activity to strong activity against Fusarium solani and demonstrated remarkably strong inhibitory activity against Candida albicans. Among all the heterocycles showed high antioxidant activity. These biological results were confirmed through molecular docking analysis utilizing different proteins. Furthermore, the optimization of these compounds was utilized through the DFT/B3LYP/6–311(G) basis set and elucidation of their descriptors and enhanced the biological activities

Interlayer-Functionalized Graphene with Phosphorus–Silicon-Containing Elements for Improving Thermal Stability and Flame Retardance of Polyacrylonitrile

Highly-effective non-halogenated flame retardants have received widespread attention because they are environmentally friendly, with low toxicity and low smoke density. In this work, interlayer-functionalized graphene (fRGO) containing silicon and phosphorus elements was synthesized via hydrolytic condensation with 3-(methacryloyloxy)propyltrimethoxysilane and addition reaction with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. Interlayer spacing and oxygen-containing groups of reduced graphene oxide (RGO) were regulated by controlling the hydrazine hydrate dosage. Then, phosphorus–silicon-containing organic molecules were inserted into RGO interlayers; this was verified by FTIR, XPS, TEM, etc. The fRGO was added to a polyacrylonitrile (PAN) matrix using a solution blending method to prepare polyacrylonitrile (PAN) composites. The fRGO addition caused the significant decrease in cyclization heat and the considerable increase in char residues, indicating improved thermal stability. Importantly, PAN composites exhibited outstanding flame-retardant properties, with the peak heat release rate reduced by 45%, which is ascribed to the dense graphitic carbon layers induced by phosphorus–silicon-containing organics and the 2D barrier effect of RGO layers to prevent the heat and mass transfer.

Design, Synthesis, Antibacterial, and Antifungal Evaluation of a New Series of Quinazoline - Thiazole and/or Quinazoline - Triazole Hybrids as Bioactive Heterocycles.

Herein, a one-pot reaction between cyclohexanone, thiourea, and 2,5-dimethoxybenzaldehyde allowed to prepare hexahydroquinazoline-2(1H)-thione4 firstly, which followed by reacting with hydrazine hydrate to produce the corresponding 2-hydrazinylhexahydroquinazoline 6. Interesting analogs of thiazolo[3,2-a]quinazoline 713 where obtained when hexahydroquinazoline-2(1H)-thione 4 reacted with 1,2-dibromoethane, chloroacetyl chloride, bromoacetic acid, bromoacetic acid/4-chlorobenzaldehyde, 2-bromopropionic acid, ethyl bromo cyanoacetate, and/or bromomalononitrile; respectively. While triazolo[4,3-a] quinazoline 14-16 were created when 2-hydrazinylhexahydroquinazoline 6 reacted with triethyl orthoformate, acetic anhydride, and carbon disulfide respectively. Numerous spectroscopy tests, including FT-IR, NMR (1H &13 C), and MS spectrum, proved all the newly produced analogs. Additionally, the new analogs were examined for their antibacterial and antifungal properties against Escherichia coli, Staphylococcus aureus, and Candida albicans. It was discovered that triazolo[4,3-a] quinazoline analogs 14-16 have superior bacterial and fungal activity when compared to the corresponding conventional doses of Streptomycin andGriseofulvin. Towards Candida albicans; compounds 14, 15, and 16 increase activity with 1.14 %, 1.15 %, and 1.21 %, respectively more than griseofulvin.While, for Staphylococcus aureus; compounds 14, 15, and 16 increase activity with 1.5 %, 1.5 %, and 1.7 %, respectively more than streptomycin. Morever, for Escherichia coli; compounds 14, 15, and 16 increase activity with 1.19 %, 1.21 %, and 1.22 %, respectively more than streptomycin. Finally, structure activity relationships show that quinazoline derivatives exhibit higher activity when fused to pyrazole ring 14-16 as compared when fused thiophene ring 7-13.

Modulation of ZrO2-Ag2O-MoO3 nanocomposite into ultrasensitive hydrazine electrochemical sensor for environmental remediation

Herein, a facile single-step wet chemical approach was executed for the composition of semiconductor ternary metal oxides (TMO) i.e., ZrO2-Ag2O-MoO3 nanocomposite (NC) in an alkaline medium. For structural as well as morphological elucidation, the calcined nanocomposite was characterized through ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), powdered X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS) and Brunauer-Emmett-Teller (BET) analysis. Later, the glassy carbon electrode (GCE) was modified into a highly responsive as well as selective hydrazine (HDZN) electrochemical probe (ZrO2-Ag2O-MoO3-NC/PEDOT:PSS/GCE) by the fabrication of thin layered ZrO2-Ag2O-MoO3 NC onto GCE facilitated by 5 % PEDOT:PSS as conducting polymer binder. While examining the analytical parameters through novel current–potential (I-V) electrochemical approach, for the first time, the newly designed electrochemical probe, as selective hydrazine sensor, happened to own the low detection limit (LOD; 0.028 pM) with greater sensitivity (33.86 μAμM−1cm−2) and broad linear dynamic range (LDR; 0.1 M–1.0 nM) in addition to coefficient of correlation (r)/r2 square (r = 0.9941, r2 = 0.9882) and low limit of quantification (LOQ; 0.093 pM). Furthermore, reproducibility as well as prolonged stability of this newly proposed probe towards hydrazine were also assessed and found to be reliable in short response time. Hence, this work presents an inaugural report about the sensing of HDZN through the newly designed non reported ZrO2-Ag2O-MoO3-NC/PEDOT:PSS/GCE via an economical as well as novel electrochemical, current–potential (I-V), approach. Additionally, this proposed method is equally responsive towards both environmental and extracted real samples analysis on large scale.

Development of a simple and safe route to C-3 arylated 1H-pyrazoles

A simple transition-metal-free and highly chemoselective strategy for the preparation of C-3 arylated 1H-pyrazoles with enaminones and p-toluenesulfonyl hydrazide (TsNHNH2) has been developed. The current environmental benign protocols showed that, TsNHNH2 could be served as the safe and easy-to-handle hydrazide for the preparation of C-3 arylated 1H-pyrazoles instead of the explosive and genotoxic hydrazine hydrate under mild conditions, with broad substrate scope and excellent functional group tolerance. More importantly, a gram-scale synthesis of a synthetic equivalent of key intermediate to immuno-oncology agonist BMS-986299 was demonstrated successfully through a simple crystallization or extraction process for the scalable production.

The Use of the Carbonyl Group (C-3) of Isatin for the Construction of Pyrazoline Moiety and the Study of its Antioxidant Activity

A series of novel pyrazoline derivatives 5-13 were synthesized in three steps from isatin, with yields ranging from 40 to 72% over the multistep procedure. The first step included the condensation of isatin with p-aminoacetophenone to afford the corresponding Schiff base 1 in a 75% yield. In the second step, the enolate form of Schiff base 1 was reacted with different aromatic aldehydes (benzaldehyde, p-nitrobenzaldehyde, and p-chlorobenzaldehyde) to give the title chalcone derivatives 2-4 in 60-72 yields. In the third step, pyrazoline derivatives 5-13 were synthesized via cycloaddition reactions between compounds 2-4 and hydrazine hydrate, phenyl hydrazine, or p-nitrophenyl hydrazine. The cycloaddition produced the target pyrazoline compounds in 40-72% isolated yields. All prepared compounds were characterized by FT-IR and 1H NMR spectroscopy. Some of the prepared compounds were tested for antioxidant properties.

Sonochemical amino-functionalization of hexagonal boron nitride nanosheets produced by liquid phase exfoliation

The functionalization of hexagonal boron nitride nanosheets (hBNNSs) is a powerful strategy to improve their properties, such as dispersibility and stability in aqueous media, biocompatibility, and surface affinity. In this work, we report the functionalization of hBNNSs using a two-step strategy. First, hBN powder was exfoliated at ambient temperature by liquid phase exfoliation method into deionized water/isopropanol mixture and the resultant hBNNSs were characterized by transmission electron microscopy, X-ray diffraction and Raman spectroscopy. In the second step, the surface of the hBNNSs was modified with amino groups by means an ultrasonic wave-assisted functionalization process using hydrazine hydrate as functionalization agent. The amino-functionalization of the hBNNSs was confirmed by Infrared (IR) spectroscopy and thermogravimetric analysis (TGA). Our results showed that in an exfoliation optimized process with a sonication time of 4 h, the yield of hBNNSs reach 66 %, and that the hBNNSs can be dispersed in water, isopropanol, and water/isopropanol 75:25 at concentrations of up to 1.5 mg/mL. IR analysis confirmed that the amino groups were successfully grafted on hBNNSs, whereas TGA curves revealed that the content of –NH2 groups in the NH2-hBNNSs vary from 0.9 to 3.2 wt% depending of functionalization agent amount. Due to the polar nature of the amino groups, the NH2-hBNNSs exhibit higher stability and dispersibility in aqueous media compared with the unmodified hBNNSs. Particularly, the NH2-hBNNSs can be dispersed in water/isopropanol 75:25 at concentration from 7 to 15 mg/mL, depending on the content of amino groups.

A Novel Synthesis Route of Phenyl Quinoline from Nitrochalcone with Hydrazine Hydrate in the Presence of Pd/C

Quinoline is widely known to have many biological activities. Therefore, the development of the synthesis method of a quinoline derivative framework is a priority. A phenyl quinoline derivative, 6,7-dimethoxy-2-phenylquinoline Q1, has been successfully synthesized via a novel one-pot reaction that involves reduction, cyclization, and followed by dehydration of nitrochalcone derivate, 3-(4,5-dimethoxy-2-nitrophenyl)-1-phenylprop-2-en-1-one C1. The reaction was carried out using 80 % hydrazine hydrate in the presence of 10% Pd/C as a catalyst in an ethanol medium. Target compound Q1 was afforded in a good yield of 69.18% in a relatively short reaction time of ±2 h.

The applications of nanocatalysts in the synthesis of heterocyclic compounds

Nanocatalysts in heterocyclic synthesis are a very important direction in producing eco-friendly compounds. These catalysts can be reused up to six times without losing their quantity and efficiency. Most of these nanocatalysts are cheap, available, economical and safe for the environment. In this review, I focused on the synthesis of furans, pyrans, chromenes and thiazoles from nanocatalysts. For example, pyranopyrazoles 8a-c were synthesized by the multicomponent reactions between aldehydes 4a-c, malononitrile (5), ethyl acetoacetate (6) and hydrazine hydrate (7) using titanium dioxide as a nanocatalyst. KEY WORDS: Heterocyclic, Chromenes, Nanocatalysts, Eco-friendly compounds Bull. Chem. Soc. Ethiop. 2025, 39(1), 123-129. DOI: https://dx.doi.org/10.4314/bcse.v39i1.10

Characterization and Synthesis of Graphite, Graphene Oxide, and Reduced Graphene Oxide Powder from Waste Dry Cell Battery Rod

In this paper, graphite, graphene oxide, and reduced graphene powders were successfully synthesized from waste dry cell batter through successive chemical solution methods. Graphite powder was extracted from the graphite electrode of waste batteries rod by acidic chemical treatment. The obtained powder was utilized as a precursor for synthesizing graphene oxide following the new modified Tour method. Eventually, reduced graphene oxide was prepared from the chemical reduction of graphene oxide (GO) by hydrazine hydrate treatment. The obtained recycled graphite, reduced graphene oxide (rGO), and GO materials have been characterized using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), photoluminescence (PL), and Raman spectroscopy effectively. All the above characterization results confirmed that graphite shows a strong peak at a diffraction angle of 26.5[Formula: see text], corresponding to the (002) plane, shifted to a lower angle of 25.2[Formula: see text] in the case of rGO. In addition, the unsmooth graphite sheet shifted to smooth and flake-like shape of the rGO’s surface morphology. The composite result revealed that different amounts of oxygen and carbon atoms are present in rG, GO and rGO. All the experimental findings ultimately launch the successful formation of exfoliated rGO and better synthesis approach was achieved.

Synthesis of some new transition metal complexes derived from tellurated formazanes

A novel series of organotellurium compounds based on formazane derivatives with a general formula of ArTeBr3 4 and Ar2TeBr2 5 [Ar = 2-[{4-hydroxy-3-methoxyphenyl}{4-nitrophenyldiazenyl}methylene amino]-5-nitrophenyl] were synthesized by refluxing mercurated formazane derivative ArHgCl with TeBr4 in two different mole ratios of 1:1 and 2:1, respectively, in dry dioxane solvent under an argon atmosphere. Compounds ArTeBr3 and Ar2TeBr2 were then reduced by the action of an ethanolic solution of hydrazine hydrate to obtain Ar2Te2 6 and Ar2Te 7, respectively. The ligand properties of bis(2-[{4-hydroxy-3-methoxy phenyl}{4-nitrophenyl diazenyl}methylene amino]-5-nitrophenyl) telluride (7) were examined toward several metal ions through its reaction with K2PtCl4, PdCl2 · 2 H2O, K2PtCl6, RhCl3 · 3 H2O, CoCl3 · 6 H2O and NiCl2, respectively. These compounds were characterized by FTIR, UV-Vis,1H and 13C{1H} NMR spectroscopy and mass spectrometry as well as by elemental analysis, thermal analysis, magnetic susceptibility and molar conductivity. The identification of the synthesized complexes 8-13 proved that the complexes of Pt(II), Pd(II) and Ni(II) have square pyramidal geometries and are diamagnetic, while the complexes of Pt(IV), Rh(III) and Co(III) have octahedral shapes with the same magnetic behavior. The telluride 7 behaves as a neutral pentadentate ligand.

Facile synthesis of azines by carboxylic acid esters as catalyst and facilitation of intersystem crossing (ISC) in azines by azine chromophore

Development of new organic synthetic methods fascinating the researchers which facilitating the increasing demands of the modern society, environmental friendly with high efficiency and low cost. The introduction of chromophores in an organic molecules facilitating intersystem crossing (ISC) to harvest both singlet and triplet excitons is also currently demanding field. We report a facile synthesis of symmetrical azines from carbonyl compounds and hydrazine hydrate with carboxylic acid esters as catalyst in methanol. This reaction presents a condensation of primary amino groups in hydrazine hydrate and carbonyl compounds took place simultaneously in a very short refluxing time. The prepared azines 1–10 were structurally analysed by various analytical techniques such as LC-MS1, H NMR13, C NMR, UV-Vis, FTIR and single crystal X-ray diffraction. Photoluminescence properties of prepared azines were recorded in CCl4 at 1 × 10−3 M and excitation range from 329 to 362 nm. The photoluminescence analysis results revealed that compounds 1–10 (except 8) were showed delayed fluorescence and 8 was showed fluorescence property. The photophysical properties of compounds 1–10 such as electron density and band gap energies was calculated by density function theory. This results revealed that the intra-molecular charge transfer occurs within the azines. The azine function in the azines enabling intersystem crossing hence, it is showing phosphorescence.

Synthesis, Characterization, and Antimicrobial Evaluation of Thiadiazole Derivatives Derived from 2-Amino-5-Thio-1,3,4-Thiadiazole

This manuscript introduces a series of novel Schiff base and heterocyc-licring compounds, focusing on derivatives of 1,3-oxazepine and thiazo-lidinone.The derivative (2-Hydroxy-N-(5-mercapto-[1,3,4] thiadiazol-2-yl)-2-phenyl-acetamide was created by reacting ethyl mandelate ester[M1] and 2-amino-5-thio-1,3,4-thiadiazole compound to produce new compound [M2] and after that, compound [M2] was reacted with hydrazine hydrate 99% in dry DMF solvent, yielding the compound (N-(5-Hydrazino-[1,3,4]thiadiazol-2-yl)-2-hydroxy-2-phenyl-acetamide [M3]. In contrast , the Schiff base compound [M4] were synthesized by reacting compound [M3] with aromatic heterocyclic aldehyde (furan-2-carbaldehyde) in the presence of glacial acetic acid as a catalyst, and then Schiff base [M4] was reacted with maleic anhydride in dry benzene as a solvent to produce (1,3-Oxazepine) derivative [M5]. Additionally, the thiazolidinone derivative [M6] was synthesized through the reaction of equimolar amounts of (N-[5-(N'-Furan-2-yl-methylene-hydrazino)-[1,3,4]thiadiazol-2-yl]-2-hydroxy-2-phenyl-acetamide [M4] with thioacetic acid compound in chloroform as a solvent. The structural formula of all derivatives was confirmed by FT-IR and (1HNMR, 13CNMR) spectroscopy. The synthesized derivatives [M1-M6] were screened for their evaluated for antibacterial activity against S. aureus, S. epidermidis, E. coli, Klebsiella sp., and the fungus Candida albicans. Dimethyl sulfoxide (DMSO) was used as the solvent. Also, the ampicillin compound was used as the standard drug for comparison.

Synthesis and EMI shielding study of Ni (II) semicarbazone driven nickel nanoparticles

Herein, we report the synthesis of nickel nanoparticles (Ni-NPs) from Ni (II) complexes of cyclic semicarbazone derivatives and their electromagnetic interference (EMI) shielding behaviour. Ni (II) complexes of cyclic semicarbazones were synthesized and characterized by various spectroscopic tools. It was observed that such complexes are excellent precursors for the synthesis of Ni-NPs when reduced by hydrazine hydrate. It is expected that the reaction kinetics will be ably normalized by the presence of semicarbazone ligand and that upon dissociation and partial consumption during nano-particle formation, will provide an added advantage of mild functionality around the particles. Overall various nickel complexes obtained from cyclic semicarbazones were tested as an effective precursor for the synthesis of Ni-NPs which were characterized by XRD, TEM, SEM, and AFM, and their magnetic behaviour was studied by VSM. EMI shielding efficiency of flexible Ni/PVA composite films showed shielding efficiency of about minus (−) 30 dB in X-band (8–12 GHz) for about 25 % loading in the PVA matrix.