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Synthetic Approaches of Prelactone and Its Analogues: A Review
In this review we have discussed the synthetic approaches of prelactones and their epimers from 1997 to date. The presence of unique molecular architecture and its high biological importance enhanced the research activity over the last two decades. Most of the syntheses involve either a chiral auxiliary, chiral pool or catalytic enantioselective approaches as a key step. Overall this review highlights the contribution from different research groups in the total synthesis of various prelactones. 2021 Wiley-VCH GmbH -
Synthetic Applications of Prins Cyclization in Natural Product Syntheses
The natural products having tetrahydropyran unit with multiple chiral centers serve as magnificent building blocks for various active pharmaceutical ingredients (APIs). Prins cyclization is one of the wonderful strategies to construct tetrahydropyran unit stereoselectively in asymmetric synthesis. In this account, we discuss our research efforts toward the synthesis of various natural products from the past two decades (20052020) by using Prins cyclization as a key step. Further, the synthetic utility of this reaction was investigated and well demonstrated on various molecules successfully. 2022 The Chemical Society of Japan & Wiley-VCH GmbH. -
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Synthesize of Indigenous Natural Ester Based Liquid Dielectrics and its Performance Evaluation in Transformers
Transformer is generally considered to be the heart of the power system. Transformers are the main equipment in the transmission and distribution network to be monitored for uninterrupted flow of power. The liquid newlinedielectrics play an important role in functioning of transformer. It serves as an effective coolant and also it determines the life of transformer. Thus, the reliability of a power transformer is largely determined by the condition of insulation. The transformer oil is the bi product of petroleum. However, the usage of petroleum oil is running out of demand and there may be a severe shortage of oil exists in future. Also during its newlineuse and disposition, transformer oil is highly dangerous to aquatic and human life due to its non-biodegradability and hence it is not environment eco-friendly. This has given scope for new alternative biodegradable dielectric fluids such as natural esters, replacing the traditional mineral oil. These vegetable-oil-based liquids are non-toxic newlineand meet all the requirements for a high temperature insulating liquid. The Partial discharge pulses present in the liquid dielectric leads to breakdown of streamer development and formation of sludge. Hence it is important to analyze the Partial Discharge properties of oils. The aim of newlinethe present work is to investigate suitability of Indigenous Natural Ester newlinebased liquid dielectrics as a liquid dielectric coolant and also to analyze newlinethe partial discharge phenomena, particularly in transformers. The results obtained are well within the IEC 62770 standards. Results shows that developed indigenous natural ester oil that has better viscosity, breakdown voltage, flash point and partial discharge properties. As a result, developed indigenous oil will be an alternate for mineral oil in newlinehigh-voltage applications. -
Synthesis, Structure, and Physical Properties of Bulk MoS2
With the discovery of graphene by Novoselov and Geim in 2004, two-dimensional (2D) materials have been extensively researched due to their bizarre promise in the fields of electronics, optics, medical, mechanics, energy conversion, and storage. Especially, 2D-layered materials consisting of atomic sheets stacked together by weak van der Waal forces have received intriguing research interest in recent years. Cutting-edge 2D materials being investigated by researchers include 2D oxides (V2O5, MoO3, LixCoO2), topological insulators (Bi2Se3, Bi2Te3, HfBr), nitrides (h-BN, MoN, Ti4N3Tx, W2N, V2N), carbides (Ti3C2, Ta4AlC3), and transition-metal dichalcogenides (MoS2, WS2). Research has proved that these materials could counterpart graphene in a variety of fields and applications. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Synthesis, structural characterization, electrochemical and photocatalytic properties of vanadium complex anchored on reduced graphene oxide
In this work, vanadium complex anchored reduced graphene oxide (rGO-VO) was successfully synthesized by coordination interaction with phenyl azo salicylaldehyde (PAS) coupled trimethoxy silyl propanamine (TMSPA). The physicochemical and microscopic properties of rGO-VO were studied with different analytical techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM) which confirmed the synthesis of rGO-VO. The electrochemical studies of rGO-VO in glassy carbon electrode demonstrated high current density because of the amazing electrochemical properties of rGO. The photocatalytic studies of anchored rGO-VO and VO(acac)2 toward MB dye indicated that anchored rGO-VO with visible light irradiated MB was degraded fast as compared to VO(acac)2. 2021 Taylor & Francis Group, LLC. -
Synthesis, Spectroscopic and DFT studies of some benzimidazole and bemzothiazole derivatives
Benzimidazole, benzothiazole and benzoxazole compounds and their derivatives having azole moieties are biologically active and are extensively used in pharmaceutical industry. Benzimidazoles / benzothiazoles scaffolds have also been widely used as −spacers and
donor/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 for 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 chelating 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 metal 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 structures 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. -
Synthesis, spectral characterization and antimicrobial studies of novel acyl hydrazones of pacetoxybenzaidehyde
Novel acyl hydrazones derived from p-acetoxybenzaldehyde and various acid hydrazides have been synthesized. Synthetic procedure is simple and convenient and affords good yield. Elemental analysis and spectral results of the products arc also reported. 2015 Scientific Publishers. All Rights Reserved. -
Synthesis, spectral and DNA/Protein binding evaluation of novel Cu(II) chelates of an NNO donor tridentate aroylhydrazone: Halogen bonding directed close packing
An NNO donor aroylhydrazone monohydrate, HFPBH2O (3-fluoropyridine-2-carbaldehyde benzoylhydrazone monohydrate) was synthesized from 3-fluoropyridine-2-carbaldehyde and benzhydrazide and physicochemically characterised. The coordination behaviour of the aroylhydrazone with the metal ion is investigated through various physicochemical techniques and it is concluded that it binds to the metal ion predominantly in the enolate resonance form, while few complexes exhibit keto form of the ligand. The structure of [Cu(FPB)(OAc)(H2O)]H2O (4a) established by single-crystal X-ray diffraction method unveiled that the metal ion has a distorted square-pyramidal geometry in this complex. The coordination sites of Cu(II) ion are occupied by azomethine N, pyridyl N and iminolate O from a monodeprotonated hydrazone moiety and the remaining two positions are occupied by two oxygen atoms, one each from acetate ion and the water molecule. Potential applications of the complexes were studied by subjecting them to DNA/protein (BSA) binding studies using electronic and fluorescence spectroscopy. The complexes were found to bind with DNA/protein (BSA) with binding constants in the order of 104 M?1 to 105 M?1. The intercalative mode of binding of the complexes with DNA was proved using spectral studies and molecular docking. Furthermore, the complex [Cu(FPB)(N3)(H2O)2] (5) was found to cleave the DNA from form I to form II during gel electrophoresis studies. 2020 Elsevier B.V. -
Synthesis, properties, and state-of-the-art advances in surface tuning of borophene for emerging applications
Being composed of boron atoms that can be maneuvered to orchestrate low planar hexagonal structures, this two-dimensional material carefully exhibits versatility and has conventional covalent bonds between each atom. Borophene has recently proliferated the scientific research community by storm, trailblazing industries from fine chemicals, electrical equipment manufacturing, and biomedical innovation up to sustainable energy. Here, we provide streamlined information and particulars about the recent advances in the evolution of borophene since its inception and the essence of its electrocatalytic applications. We first introduce the sophisticatedly cultivated progress in borophene's structural, mechanical, optical, and electrical properties and further discuss its variegated polymorphism. Subsequently, we also delve into several capable synthesis techniques and recently concocted surface tuning and doping methods. Finally, we analyze the advancing state-of-the-art applications of this two-dimensional nanomaterial under investigation, ranging from bioimaging, energy storage, electrode reduction, and electrochemical sensing. Further, we have broadly discussed the future insights and challenges that borophene brings. 2024 -
Synthesis, Properties and Applications of Polymer Nanocomposites-A Review
Polymer nanocomposites have been a rapidly expanding research topic for producing materials over the last few decades. In the previous two decades, there has been a significant scientific interest in nanoscience and nanotechnology. Nanomaterials' distinct features are related to quantum phenomena, greater surface area, and self-assembly. Quantum effects can begin to dominate matter's behaviour in the nanoscale, particularly at the lower end, affecting optical, electrical, and magnetic properties. Nanomaterials have evolved into nanocomposites with numerous applications. Its applications catapulted them to prominence in the field of material research. Because of their unique property combinations and design practicality, polymer nanocomposites are employed in sports equipment, wastewater treatment, the automobile industry, and biomedical applications. Even though they have numerous advantages, producing them in sufficient quantities and high quality is still one of the biggest challenges. During the last few decades, polymer nanocomposites have been a fast-developing research topic for material production. There has been a surge in scientific interest in nanoscience and nanotechnology during the last two decades. Nanomaterials have developed into nanocomposites, which have a wide range of uses. Its uses propelled them to the forefront of material research. Nanocomposites physical, mechanical, barrier, flame retardancy, optical, dielectric, rheological, and thermal characteristics have been thoroughly researched. Their uses have also been discussed. 2024, Informatics Publishing Limited. All rights reserved. -
Synthesis, Process Parameter Control and Performance of Nano Ceramic Coatings for Diesel Engine Applications
Ceramics are non-metallic inorganic solids which are used in various forms (bulk and newlinecoatings) and environments (low and high temperature) to provide protection from newlinethermal, wear or chemical attack. Due to their high melting point, compressive newlinestrength, oxidation and corrosion resistant properties, ceramics are strong, hard, newlinebrittle and harsh environment resistant. Ceramic coatings are generally applied on newlinemetal components to either enhance their life or augment the performance of the devices they are mounted on. Furthermore, coatings being thin (few small units to hundreds of microns); they do not demand significant alteration in component design. Among the many types of coatings used in engineering applications, Thermal Barrier Coatings (TBC) and wear resistant coatings (WRC) are used to protect metallic components from thermal and mechanical damages respectively. 6 to 8%Yttria stabilized zirconia (6-8% Y2O3-ZrO2), generally designated as 8YSZ has been newlineextensively used as TBC and alpha alumina (and#945;-Al2O3) find applications as WRC. 250 to 300m thick micron grained TBC, with grain sizes typically up to 20 m or even higher are well known to thermally insulate diesel engine combustion chamber to provide enhanced fuel efficiency characteristics. 8YSZ and and#945;-Al2O3 coatings also find use in power plants, textiles, automotive and aero-space industries etc. to provide benefits like improved product quality and energy efficiency, extended wear life, reduced maintenance cycles and costs etc. Among ceramic coatings, nanostructured coatings have received further interest because of their extraordinary properties including enhanced hardness, strength, ductility, and toughness when compared with coatings with micron grained newlinemicrostructure. Nanostructured zirconia is also expected to serve as advanced TBC in newlineengine applications, although information on its feasibility and the technology is mostly classified. -
Synthesis, Photophysical, and Computational Studies of Mono-Azo-Bridged, Meso-Tris(2-Furyl/2-Thienyl) Substituted Porphyrin-Arene Hybrids
Porphyrins hybrids have been used as models to study various energy/electron transfer processes. The linkers connecting various subunits in such hybrids are vital in establishing good electronic communication between the subunits and the azo-bridge can be one of the efficient linkers to do so. Despite of these, the mono azo-bridged porphyrin-arene hybrids reported in the literature are only handful and the methods used to create them are not that efficient. In addition, the porphyrins used in this field so far contains only six-membered meso-substituents. By keeping these points in mind, we have developed a mild, one-pot, work-up-free, high-yielding method to synthesize mono-azo-bridged, porphyrin-arene hybrids which also features porphyrins containing three five-membered substituents like 2-furyl or 2-thienyl on their meso-positions. Along with the NMR and mass characterizations, the photophysical and computational studies of all the reported hybrids are presented. The hybrids containing meso-tris(2-furyl/thienyl) substituted porphyrins displayed red-shifted absorption and emission bands compared to their all-meso-aryl-containing counterparts. In general, all the hybrids displayed enhanced fluorescence quantum yields compared to their precursor porphyrins. Among the series, the meso-tris(2-furyl) substituted porphyrin-arene hybrids exhibited the more significant Stokes shift and small bandgap. The computational studies were in good agreement with the experimental findings. 2024 Wiley-VCH GmbH. -
Synthesis, mechanisms, challenges, and future prospects of Ti3C2 MXene and its heterojunctions for photocatalytic dye degradation efficiency: a comprehensive review
In recent years, significant attention has been given to developing novel two-dimensional (2D) materials, including MXenes. Titanium carbide (Ti3C2) is one such MXene with a bandgap ranging from 0.92 eV to 1.75 eV. MXenes possess unique physical and chemical properties that make them useful in various applications, including electrocatalysis, supercapacitors, semiconductors, batteries, sensing, biomedicine, water splitting, and photocatalysis. Research on environmental photocatalysis has focused on enhancing properties such as high conductivity, structural stability, and morphology. However, a single catalytic material may not be sufficient to achieve high catalytic efficiency. Hence, there is a need to modify MXenes. This review provides an overview of the various synthesis methods of MXene and their remarkable properties. It also discusses recent advances in MXene composites and catalytic mechanisms for dye degradation. To improve the catalytic performance of MXene, a heterojunction and Schottky junction are proposed. 2023 Elsevier Ltd -
Synthesis, Mechanical Properties and Thermal Stability of Polydimethylsiloxane Nanocomposites
The polydimethylsiloxane/nano-graphite (PDMS-NG) nanocomposites were prepared via a two rolled mixing mill and subjected to characterization using techniques such as Transmission Electron Microscopy (TEM), stress-strain analysis during elongation, as well as thermal properties including Thermo-Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The transition temperature was observed to be below-70C for PDMS nanocomposites reinforced with Nano-Graphite (NG). The thermogram from the thermo-gravimetric analysis indicated that at 10%, 20%, 30%, and 50% weight loss, the temperatures for PDMS nanocomposites were higher compared to unfilled PDMS. These findings suggest a substantial improvement in the thermal stability of PDMS-NG nanocomposites. 2023, Books and Journals Private Ltd. All rights reserved. -
Synthesis, in vitro and theoretical studies on newly synthesized deep blue emitting 4-(p-methylphenylsulfonyl-5-aryl/alkyl)oxazole analogues for biological and optoelectronic applications
In the present study, a series of 4,5-di-substituted oxazole derivatives (compounds 2a-p) were synthesized, using a novel methodology for the simultaneous determination of their biological and optoelectronic applications. Among the screened molecules, compounds 2j, 2 l and 2o showed very good antimicrobial potencies with MICs up to 1 g/mL. Furthermore, the photophysical parameters were estimated using theoretical and experimental techniques for optoelectronic applications. The excited-state dipole moment being higher than that of the ground state, investigated using solvato-chromatic method showed a redistribution of the electron densities in the excited state for the fluorophores. The HOMO-LUMO energies of the fluorophores estimated by using density functional theory (DFT) are found to be in good agreement with the experimental values. The electrophilic and nucleophilic sites were also recognized with the help of molecular electrostatic potential 3D plots using time-dependent-DFT computational analysis. The specific and non-specific interactions between the solutesolvent were analyzed by multiple linear regression analysis using Kamlet-Abound-Taft and Catalan parameters. Further, the global chemical reactivity descriptor parameter was also calculated. The photophysical properties of the fluorophores suggest that these may be considered as potential probes for OLED, solar cell, and chemosensor applications. 2022 Elsevier B.V. -
Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets /
Journal Of Applied CrystalloGraphy, Vol.47, Issue 6,pp.1841-1848, ISSN No: 1600-5767. -
Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets
The physical vapour deposition (PVD) method has been employed to yield gallium telluride (GaTe) platelets. The morphology and growth mechanism of these platelets were investigated with the aid of scanning electron micrographs. The stoichiometry and homogeneity of the grown samples were confirmed by chemical analysis. The X-ray diffraction (XRD) technique has been used to explore the structure and phase of the compound. On the basis of the Archimedes principle, the density of crystals was estimated to be 5.442 kg mm-3. The resistivity and conductivity type were determined by the van der Pauw method. UV-vis-NIR studies revealed a direct transition with an energy gap of 1.69 eV. Mechanical properties such as microhardness, toughness, Young's modulus and elastic stiffness constant of GaTe crystals in response to the stress field due to an external load were studied to realize their suitability for radiation detector applications. The present observations provide an insight into the physical properties of the vapour-grown GaTe platelets, which are found to be superior over their melt counterparts. 2014 International Union of Crystallography.