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Synthesis, crystal structure and photophysical properties of (E)-4-(4-(2-hydroxybenzylideneamino)benzyl)oxazolidin-2-one
A new Schiff base, (4-(benzylideneamino)benzyl)oxazolidin-2-one has been synthesised from 4-(4-aminobenzyl)oxazolidin-2-one and salicylaldehyde by a simple condensation reaction. Single-crystal X-ray analysis of (E)-4-(4-(2-hydroxybenzylideneamino) benzyl)oxazolidin-2-one (HBOA) revealed that there is a 1-D, slipped, face-to-face motif with off-set, head-to-tail stacked columns. Detailed studies on photophysical properties of the synthesised compound in solutions indicate their potential applications in the field of organic light emitting devices and nonlinear optical materials. Absorption and fluorescence study of HBOA has been conducted in a series of solvents with increasing polarity at room temperature. Ground and excited state dipole moments have been determined experimentally by using LippertMataga polarity function, Bakhshiev solvent polarity parameter, KawskiiChammaViallet solvent polarity parameter and Richardt?s microscopic solvent polarity parameter. Due to the considerable ?-electron density redistribution, the excited state dipole moment was found to be larger than that of the ground state. The ground state dipole moment value was determined by quantum chemical method which was used to estimate excited state dipole moment through solvatochromic correlations. KamletTaft and Catalan methods were used to get the information of both non-specific solutesolvent interactions and hydrogen bonding interactions. TD-DFT (B3LYP/6-311G(d,p)) has been used for the determination of HOMOLUMO energies. Mulliken charges and Molecular electrostatic potential were also evaluated from DFT calculations. 2016 Elsevier B.V. -
Synthesis, Computational, and Photophysical Probing Studies on Mono-Azo Sulfonamides, and Their Antibacterial Activity
Abstract: Objective: Novel azo-linked substituted sulfonamides were synthesized via diazo coupling with the molecular formula (C9H10N4O2S2, C11H11N3O2S) and characterized by FT-IR, UV-vis, HR-MS, and 1H NMR spectroscopy techniques. The photophysical studies were carried out using experimental techniques. Absorption and fluorescence maxima of all the synthesized molecules were determined by using different solvents. Our synthesized mono-azo derivatives are interested in identifying the cellular target site for sulfonamides (F1-F2) and (P1-P2). The newly synthesized compounds were examined for their in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli strains. Methods: In this study, we focused on the sulfonamide architecture. Antibacterial activity of compound (F1), (F2), (P1), and (P2) derivatives was studied by measuring the diameter of the inhibition zone, using the Disc-agar diffusion method. Results and Discussion: Density functional theory was used to demonstrate the electronic and optical properties of the synthesized molecules. In the correlation between the HOMOLUMO energy gap, the derivative (F1) shows a higher (3.9866 eV) and (F2) shows a lower (3.2063 eV) excitation energy. The synthesized compound (F1) looks into antibacterial activity, exhibited more zone inhibition 25 mm in the concentration 75 L/mL in gram-negative bacteria when compared with the common antibiotic Ciprofloxacin. Additionally, the results emerged from the in silico molecular docking studies the compound (F2) showed highest binding energy against cyclin-dependent kinase (?Gb = 9.8 kcal/mol). Conclusions: The synthesized four mono-azo sulfonamide derivatives (F1), (F2), (P1), and (P2) are reported in photophysical, CDFT, antibacterial, and molecular docking studies with relevant results. Pleiades Publishing, Ltd. 2024. -
Synthesis, characterizations, and electrochromic studies of WO3 coated CeO2 nanorod thin films for smart window applications
In this work, Cerium oxide nanorods were synthesized on Fluorine doped Tin oxide (FTO) substrate by a hydrothermal technique involving Ce(NO3)36H2O (Cerium Nitrate Hexahydrate) and CH4N2O (Urea). The DC magnetron sputtering was used to deposit a thin layer of WO3 on Cerium Oxide nanorods in the presence of argon gas at room temperature. With the prepared CeO2/WO3 thin films as the working electrode, saturated AgCl2 as the reference electrode, and platinum mesh as the counter electrode, a three-electrode electrochemical cell was developed with 0.5 M H2SO4 solution diluted in deionized (DI) water as the electrolyte. The electrochromic studies displayed a coloration efficiency of 10.14 cm2/C for 0.1 M film. SEM, UVVisible, XRD, and electrochemical analyzer were used to investigate the surface morphology, optical properties, composition, and electrochromic performance of the prepared thin films. A combination of CeO2 nanorods and WO3 coating has been proved to be a potential material for Electro Chromic Devices (ECD), because of its large charge capacity and optical transmission behavior. 2022 Elsevier B.V. -
Synthesis, characterization, magnetic, thermal and electrochemical studies of Oxovanadium(IV) Complex of 2-thiophenecarba benzhydrazone
The hydrazone ligand obtained from 2-thiophene carboxaldehyde and benzhydrazide react with an equimolar mixture of vanadyl acetyl acetonate in methanol to yield oxovanadium(IV) complex of 2-thiophenecarba benzhydrazone. The prepared compound shows effective solubility in organic solvents like acetonitrile, DMF and DMSO. Molar conductivity data of oxovanadium( IV) complex of 2-thiophenecarba benzhydrazone revealed its nonelectrolytic behavior in DMF and DMSO. EPR spectra of 2-thiophenecarba benzhydrazonato oxovanadium(IV) was recorded in DMF at LNT and g and A values were calculated. The complex was proposed to be square pyramidal in geometry. Cyclic voltammograms of the complex in DMF were studied by changing the scan rates 50, 100, and 200 mV/s. ? E values of the complex showed the reversible criterion and ipc/ipa values which were close to 1 indicating the redox couple as reversible. Thermograms of the complex were recorded to find the weight loss at different temperature ranges. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectra showed mass number of the molecular ions. 2018 River Publishers. -
Synthesis, Characterization of Chromium Oxide Powders and Coatings
The chromium oxide powders are transformed into plasma sprayable particles by using synthetic polymers for agglomeration. In order to carry out the agglomeration process, spray drying technique was employed. This research work highlights the significance of the process variables that control the synthesis of plasma spray powder and consequently, the properties that were suited for plasma sprayoating. Energy Dispersive Spectroscopy (EDS) was used to characterize the elemental composition, while scanning electron microscopy (SEM) was used to analyse the morphology and powder grain sizes and X-ray diffraction (XRD) was used to identify the phase structure. And for the development of coatings on the substrates, Atmospheric plasma spray (APS) technique was used. The plasma sprayable powders were created with the intention of investigating for use as corrosion-resistant coatings. 2023 Trans Tech Publications Ltd, All Rights Reserved. -
Synthesis, Characterization and Studies of Hydrazine Based Polyfunctional Ligands and their Metal Chelates
Eight new hydrazine-based zinc (II), copper (II) complexes were synthesized by reacting Zn (OAc)2.2H2O and Cu(CH3COO)2 with N'??(3,5-dibromo-2-hydroxy benzylidene) benzohydrazide (H2L1) and N'??(3,5-dibromo-2-hydroxy benzylidene) nicotinichydrazide (H2L2) respectively. The synthesized complexes were characterized by CHN analyses, IR, UV and 1H NMR. Based on these studies, square planar and octahedral geometries of the metal complexes were revealed. The synthesized metal complexes named [Zn(H2L1)2](OAc)2, [Zn(H2L1)Py](OAc)2, [ZnL2]2, [ZnL2Py], [CuL1]2, [CuL1Py], [CuL2]2 and [CuL2Py]. The formed metal complexes were investigated for DNA binding studies by fluorescence and UV spectroscopy using calf thymus DNA (CT-DNA) and DNA cleavage studies against pBR322 DNA. Both the ligands and their corresponding metal complexes showed the ability for binding to DNA through intercalation/ electrostatic binding. -
Synthesis, characterization and photophysical studies of a novel schiff base bearing 1, 2, 4-Triazole scaffold
A novel Schiff base derivative containing 1, 2, 4-triazole nucleus (TMPIMP) was synthesized from 4- [1,2,4] triazol-1-ylmethyl-phenylamine and salicylaldehyde in the presence of glacial acetic acid in an ethanolic medium. The synthesized compound was characterized by 1H-NMR, IR and UV spectral analysis. The excitation and emission spectra of triazolyl methyl phenyl imino methyl phenol (abbreviated as TMPIMP) were recorded in various solvents to investigate their solvatochromic behaviour. Dipole moments of the two electronic states of TMPIMP were calculated from solvatochromic spectral shifts. These were correlated with refractive index (?) and dielectric constant (?) of various solvents. Theoretical calculations were performed to estimate the excited state dipole moment on the basis of different solvent correlation methods, like the Bilot-Kawski, Bakhshiev, Lippert-Mataga, Kawski-Chamma-Viallet and Reichardt methods. The dipole moment in the excited state was found to be higher than that in the ground state due to a substantial redistribution of electron densities and charges. Using a multiple regression analysis, the solvent-solute interactions were determined by means of Kamlet Taft parameters (?, ?, ??). Computational studies were performed by Gaussian 09 W software using a time-dependent density functional theory (TD-DFT) in order to calculate the atomic charges and frontier molecular orbital energies in the solvent phase. The calculations indicated that the dipole moment of the molecule in an excited state is much higher than that in a ground state. The chemical stability of TMPIMP was determined by means of chemical hardness (?) using HOMO-LUMO energies. The reactive centers in the molecule were also identified by molecular electrostatic potential (MESP) 3D plots as a result of TD-DFT computational analysis. 2016 Elsevier B.V. All rights reserved. -
Synthesis, characterization and crystal structure of N'-[(E)-furan-2-ylmethylidene]furan-2-carbohydrazide /
European Journal of Chemistry, Vol.5, Issue 3, pp.174-176, ISSN No: 2153-2249. -
Synthesis, characterization and catalytic activity of oxovanadium(IV) complexes of heterocyclic acid hydrazones
Two acid hydrazones, furan-2-carbaldehyde nicotinic hydrazone (L1) and furan-2-carbaldehyde benzhydrazone (L2) have been synthesized and they are characterized by elemental analysis, IR, NMR and UV spectral analysis. Oxovanadium(IV) complexes of these two hydrazones were synthesized and characterized by elemental analysis, IR, UV, EPR, molar conductivity and magnetic susceptibility measurements. Conductivity measurements reveal that the complexes are non-electrolytes. Spectral data indicates the square pyramidal geometry for the monomeric five coordinated oxovanadium(IV) complexes with the general formula [VO(L)(OCH3)]. The complex was studied for its catalytic activity and was found to be a good catalyst in quinoxaline synthesis. -
Synthesis, characterization and biological activity studies on 6-p-dimethylaminophenyl-5,6-dihydrobenzoimidazo [1,2-c]quinazoline: Crystal structure of the title compound and comparative study with related derivatives
Reaction of o-aminophenylbenzimidazole with p-dimethylaminobenzaldehyde yielded 6-p-dimethylamin-ophenyl-5,6-dihydrobenzoimidazo[ 1,2-c]quinazoline, which was characterized by elemental analysis, IR, UV-Vis, 1H NMR, 13C NMR, mass spectral studies and X-ray crystal structure analysis. Studies on the antimicrobial activity of the compound revealed that it is active against fungus Yeast but not Bacillus subtilis. The compound crystallized in the space group P2 1/n with the unit cell parameters a = 10.652(2) b = 11.002(2) c = 15.753(2) ? = 109.29(2) and the structure was refined to an R-factor of 0.0479. The hydropyrimidine ring in the quinazoline moiety is in skew-boat conformation. The dimethylamino group attached to phenyl ring is in conjugation with it. The structure was stabilized by intermolecular C-H-N interactions. A few of the related quinazolines (6-p-hydroxyphenyl-5,6-dihydrobenzoimidazo [1,2-c]quinazoline; 6-phenyl-5,6-dihydrobenzoimidazo[1,2-c]quinazoline; 6-pyridyl-5,6- dihydrobenzoimidazo[1,2-c]quinazoline; 6-furyl-5,6-dihydrobenzoimidazo[1,2-c] quinazoline) were also examined for their biological activity, in addition to their characterization by IR, UV-Vis, JH and 13C NMR spectral studies along with structural comparison. Springer Science+Business Media, LLC 2011. -
Synthesis, characterization and application of rare earth (Lu3+) doped zinc ferrites in carbon monoxide gas sensing and supercapacitors
The novel rare earth (Lu) doped zinc ferrite nanoparticles, synthesized via a solution combustion approach, exhibit exceptional sensitivity to carbon monoxide (C.O.), a capability studied for the first time. The successful detection of C.O. by these nanoparticles underscores their potential as efficient gas sensors. Structural and morphological characterization confirmed the creation of single-phase zinc ferrite nanoparticles, utilizing various standard and advanced modern probes. To assess the gas sensing capabilities, the nanoparticles were exposed to carbon monoxide gas, revealing an outstanding gas response of 80 % at 300 C, with a response against 20,000 parts per million by volume (PPMv) of carbon monoxide. These results indicate the promising applicability of Lu-doped zinc ferrite nanoparticles in C.O. gas sensing applications. Furthermore, the supercapacitance performance of the synthesized nanoparticles was investigated. Electrodes fabricated from Lu-doped zinc ferrite nanoparticles (Lu 0, 0.3, 0.5, and 0.7) were examined in a 3 M K.O.H. electrolyte using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (E.I.S.). The electrochemical properties of all nanoparticles exhibited good Faradaic behaviour, with the Lu 0.7 electrode achieving a high specific capacitance of 280 F/g at a current density of 0.25 A/g. This highlights the prominent electrochemical stability and potential applications of Lu-doped zinc ferrite nanoparticles in energy storage devices. Overall, the comprehensive investigation of the gas sensing and super capacitance performance of Lu-doped zinc ferrite nanoparticles demonstrates their versatility and potential for various technological applications, including gas sensing and energy storage. These findings pave the way for further research and development in utilizing rare earth-doped ferrite nanoparticles for advanced functional materials. 2024 Elsevier Ltd and Techna Group S.r.l. -
Synthesis, characterization and antimicrobial studies of novel Schiff bases and their complexes
Novel Schiff bases, Furan-2-carboxylic acid pyridin-4-ylmethyleneamide, and Thiophene-2-carboxylic acid 1H-indol-2-ylmethyleneamide and their mononuclear Ni(II) and Cu(II) complexes have been synthesized and characterized by elemental analysis, molar conductance, UV-visible, FT-IR, 1H NMR and EPR spectroscopy. The complexes are non-electrolytes as evidenced from the molar conductance vaules. The ligands and their complexes have been tested for their antimicrobial activity against one gram positive bacteria, Bacillus subtilis, gram negative bacteria, Escherichia coli and fungi Candida albicans. It is found that metal complexes exhibited more activity than the free ligand. 2021 Scientific Publishers. All rights reserved. -
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Synthesis, Characterization and Analytical Applications of Disubstituted urea/thiourea derivatives
Two Urea/Thiourea derivatives have been synthesized in good yields from Urea/Thiourea and aniline in dry media conditions by using p-TSA as catalyst under microwave assisted method and they are characterized by IR and NMR spectral analysis. There are several advantages of foresaid catalyst like rate enhancements, higher yields, easy work-up procedure and energy efficient. The reaction has been done under solvent free condition having short reaction time period, increased safety and economic advantages. This Thiourea derivatives reagent has been used for the spectrophotometric determination of palladium. The results obtained by the proposed method is accurate reproducible. The proposed method has been successfully applied for the determination of palladium(II) in some synthetic mixtures of alloy samples and mineral. This dissertation contain five chapters Chapter 1 includes significance of Urea/Thiourea derivatives, green experimental protocol, heterogeneous catalysts. It also includes Objective of the study which is a develop a new methodology for the synthesis of Urea/Thiourea derivatives. Chapter 2 includes review of literature on the synthesis of Urea/Thiourea derivatives by different varieties of techniques. Different catalysts are used for that technique. Chapter 3 describes about materials and experimental procedures which are used in this synthesis . Chapter 4 deals with the various characterization results of Urea/Thiourea derivatives. It also describes the application of N,N??-diphenylthiourea in the trace level determination of palladium. Chapter 5 gives the summary and conclusion of the present study. It also gives the future scope of the present work. Furthermore, short reaction times, good yields of products, mild reaction conditions, and easy work-up/purification are the other noteworthy advantages which make this method a valid contribution to the existing methodologies is given in this chapter. Key works: Urea/Thiourea derivatives, p-TSA, MWI, IR, NMR, and Palladium. -
Synthesis, Characterization and Catalytic activity of Zirconia-Ceria catalysts
The development of catalysts is critical for the economical and environmentally efficient generation of chemical compounds that underlie every aspect of our society. Catalysts are key players in research involving the discovery of pharmaceuticals, materials, and polymers. In addition, catalysis is especially powerful in bulk synthesis, allowing the production of compounds, polymers and commodity chemicals via routes that would otherwise be impossible. Ceria is the unique rare earth for which dioxide is the normal stable phase contrary to the others for which Ln2O3 is the normal stoichiometry. The applications of ceria based materials are related to a potential redox chemistry involving Ce(III) and Ce(IV), high affinity of the element for oxygen and sulphur and absorption/excitation energy bands associated with its electronic structure. Zirconium is one of the more abundant elements, and is widely distributed in the Earth's crust. Being very reactive chemically, it is found only in the combined state or as part of a complex of oxides as in zircon, elpidite, and eudialyte. Doping ceria with zirconia may improve the oxygen storage properties of ceria at three different levels. At the level of the microstructure, it inhibits surface diffusion and in turn the loss of surface area at high temperatures. At the microscopic level, substantial doping may result in the formation of an interface structure that facilitates the oxygen transport from bulk to the surface. At the atomic-level, it stabilizes the oxygen defective structure. The texture, structure and thermal stability of ceria-zirconia doped oxides are closely related to the ratio of cerium to zirconium in the solid solution. Chapter 1 comprises of the general introduction of catalysis, importance of solid acid catalysis, sulphated metal oxides, pure ceria, pure zirconia, modified ceria and zirconia. It gives a brief introduction about the nitration of toluene. The aim and objectives of the present investigation are also described at the end of this chapter. Chapter 2 comprises of a thorough literature survey on the significance of solid acid and super acid catalysts in various domains of chemical industry and importance of anion promoted zirconia and ceria catalysts. The definition of ??super acid and their classification vii on the basis of origin of the active sites are also outlined. Importance of modified metal oxides is also outlined. Chapter 3 deals with the experimental procedures and techniques employed in this investigation. Scientific aspects of the precipitation and impregnation methods were outlined. The experimental details of surface area measurements by BET method, application of X-ray powder diffraction studies for crystalline phase and size determination, elemental detection by EDAX, spectral details from FTIR and thermal stability by TGA have been described. Chapter 4 deals with the various characterization results and discussion of pure, doped and sulphated Zirconia-ceria solid acid catalysts. The bulk and surface properties of the catalyst was discussed by XRD, BET surface area, TGA and FTIR. All characterization results revealed that the incorporated sulphate ions has a significant influence on the surface and bulk properties of the ZrO2-CeO2 catalyst. The prepared catalysts are investigated for the liquid phase nitration of toluene under various reaction conditions. Chapter 5 gives with the summary and conclusion of the present study. It also gives the future scope of the present study. On the whole, zirconia-ceria solid acid catalysts were successfully synthesized by simple route. Physicochemical characterization of all these catalysts revealed that the loaded sulphated and doped metal oxides show a significant influence on the surface and bulk properties of the ZrO2 - CeO2. These catalysts are found to be active for the liquid phase nitration of toluene. Key words: Solid acid catalysis, Zirconia-Ceria, Sulphated zirconia-ceria, Nitration of toluene -
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Synthesis, Adsorptive Properties and Applications of Modified Aluminum Oxyhydroxide-PVA Films
Over the past few years, there has been an increasing interest in polymer films and newlinemetal-incorporated polymer films because of their distinctive characteristics and newlinepotential applications. The effectiveness of alumina or modified alumina polymer films newlineas adsorbents or catalysts is greatly influenced by their surface properties, texture, chemical composition, and thermal stability. This thesis describes the synthesis of aluminum oxyhydroxide - polyvinyl alcohol composite films by sol-gel method. The synthesized films were modified by incorporating transition metals and cross-linking agents depending on the desired application as a catalyst or adsorbent. The synthesized films were characterized using different techniques, like powder X-ray diffraction studies (pXRD), Fourier transform infrared spectra (FTIR), Raman spectra, BrunauerEmmett-Teller surface area (BET), Barrett-Joyner-Halenda (BJH) isotherm, atomic newlineforce microscopy, optical profilometry, thermogravimetric analysis, Scanning electron newlinemicroscopy (S.E.M), and X-ray photoelectron spectroscopy (XPS) to determine the newlinestructural and textural properties. The films were deployed as adsorbents for the removal of heavy metals and dyes from water as well as catalysts for industrially important organic transformations. The results of the characterization studies were used to correlate the surface characteristics and adsorptive capacities of the fabricated films. The films were found to have tuneable surface properties and enhanced adsorptive newlinebehaviour, which could be modified as per the application. Transition metalincorporated films exhibited remarkable adsorption properties for the elimination of heavy metals and organic dyes from aqueous solution. The adsorption reaction kinetics newlinewere investigated to ascertain the rate and mechanism of the reaction to improve the newlineefficiency, economic efficiency and environmental sustainability of the reaction. -
Synthesis spectroscopic and DFT studies of some benzimidazole and benzothiazole derivatives
Benzimidazole, benzothiazole and benzoxazole compounds and their derivatives having azole newlinemoieties are biologically active and are extensively used in pharmaceutical industry. newlineBenzimidazoles/benzothiazoles scaffolds have also been widely used as and#61552;and#8722;spacers and newlinedonor/acceptor units. The lone pair electrons and conjugated structures of these heterocyclic molecules assist in tuning of electronic properties enabling their use in devices like dye sensitized solar cells, organic light emitting diodes etc. However, the design and synthesis of organic ligands newlinefor these applications is still a challenging task. Though we have made an effort in this direction fabricating a dye sensitized solar cell with benzimidazole based sensitizer, the moderate Stokes shift and efficiency prompted us to tune these molecules and improve their electronic properties. Considering that some of the benzimidazole/benzothiazole fluorophores possessing metal-ion newlinechelating properties and having hydrogen donor-acceptor sites in close proximity play vital role in sensor and bioimaging applications, we have designed and synthesized novel fluorophores for newlinemetal ion sensing applications. Since most of the available literature shows studies on fluorophores with single excited state intramolecular proton transfer sites or dual proton transfer sites with symmetrical structures, we have considered investigating fluorophores having asymmetrical newlinestructures and proton donating sites. In this perspective, we have synthesized and conducted spectroscopic and density functional theory studies on some novel fluorophores based on benzimidazole/benzothiazole Schiff bases and the details are presented in this thesis. Chapter 1 gives an introduction to the benzimidazole/benzothiazole heterocycles and the different photophysical and chemical phenomena involved. A brief literature survey in support of our studies is presented in Chapter 2. Chapter 3 gives a brief description of the experimental methods newlineand techniques used in our work. -
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Synthesis of ZnO and NiO nano ceramics composite high-performance supercapacitor and its catalytic capabilities
NiO and ZnO mixed nanocomposites were manufactured using the solution combustion process. As-prepared samples were analyzed using XRD. The XRD shows an average crystallite size of 3540 nm. The elemental composition determined by EDS indicates a nearly equal proportion of Ni and Zn, with an atomic ratio of Ni/Zn = 0.96. The specific capacitances of NiO is 295.5 Fg-1, ZnO is 117.3 Fg-1 and ZnO/NiO nanocomposites is 561.75 Fg-1 which are more than NiO and ZnO alone. This study shows that constructing binary oxide nanocomposites is an approach for developing high-performance supercapacitor electrode materials. Experimental observations on catalytic activity revealed that NiO/ZnO increased catalytic activity. Furthermore, adding NiO to ZnO in the composite increased the overall amount of oxygen vacancies in the samples. Our research lays the door for a simple, inexpensive, nontoxic, and quick technique to synthesize binary transition metal oxide-based electrode materials for high-performance supercapacitors. 2024 Elsevier Ltd and Techna Group S.r.l.