Research on Chemical Intermediates最新文献

Calcium ferrites (CaFe₂O₄) have emerged as a promising class of materials due to their unique properties, including high chemical stability, eco-friendliness, and biocompatibility. This review thoroughly examines recent developments in the synthesis and uses of nanomaterials based on CaFe₂O₄, with an emphasis on their use in energy storage, medicinal sectors, environmental remediation, and heterogeneous catalysis. It is examined how well CaFe₂O₄ performs in supercapacitors and battery technologies, as well as its catalytic efficiency in a variety of organic transformations and pest destruction. Additionally, a critical evaluation is conducted on the potential of calcium ferrite in drug delivery, antibacterial, and hyperthermia applications. Even with its potential, problems like poor electrical conductivity and scalability still exist. Additionally, these limitations are discussed in this review along with potential future strategies for improving the performance of calcium ferrite-based systems. The goal of this work is to serve as a useful resource for researchers looking to develop effective and sustainable nanomaterial-based solutions by highlighting the numerous uses and enduring difficulties.

Toxic heavy metals (Pb²⁺/Cd²⁺) bioaccumulate in aquatic systems, posing severe health risks that necessitate efficient adsorbents for water purification. Hence, this study investigated the performance of the composite derived from rice straw-derived biochar (RSB) and MgAl-layered double hydroxide (LDH) for removing Pb²⁺ and Cd²⁺ from aqueous solutions. The morphological, elemental, crystalline, and surface properties of the co-precipitated RSB-LDH composite were comprehensively assessed through FE-SEM, EDS, XRD, FTIR, and BET techniques. The simultaneous effects of pH, initial heavy metal concentrations, adsorbent dosage, and contact time were optimized through response surface methodology, based on a central composite design. The analysis of variance confirmed the adequacy of the model, with R² values of 0.9699 and 0.9573 for Pb²⁺ and Cd²⁺, respectively, demonstrating the maximum removal efficiencies of 100% for Pb²⁺ and 97.71% for Cd²⁺. The optimal conditions for maximum Pb²⁺ removal occurred in pH 5.40, with an initial concentration of 22.37 mg/L, an RSB-LDH dosage of 0.94 g/L, and a contact time of 37.65 min. In contrast, the optimal conditions for Cd²⁺ removal were pH 5.68, an initial concentration of 7.03 mg/L, an RSB-LDH dosage of 1.31 g/L, and a contact time of 58.93 min. The pseudo-second-order kinetic equation and Langmuir model well fit the adsorption kinetic data and isotherm data, respectively. The RSB-LDH adsorbent exhibited remarkable regeneration capability, preserving over 85% removal efficiency for both ions after five cycles. These results highlight RSB's crucial role in developing the RSB-LDH composite, which exhibits excellent adsorption performance with reusable capabilities for removing toxic Pb²⁺ and Cd²⁺ ions from contaminated water.

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In this study, a bio-based and environmentally benign CS-g-PAN nanomaterial comprising of acrylonitrile as a crosslinking agent, chitosan as a backbone, and ammonium persulfate as a mild initiator was developed through a modified procedure. Various spectroscopic, microscopic, and analytical methods were employed to study the structure of easy handling prepared nanocomposite including FTIR, EDX, XRD, FESEM, BET, TGA, and DTA. The synthesis of 2-amino-3-cyano-4H-pyran derivatives can be accomplished efficiently by employing CS-g-PAN, as a nano-ordered organocatalyst, through the multicomponent reactions strategy. A wide range of aldehyde derivatives, malononitrile, and dimedone or ethyl acetoacetate were involved smoothly under the optimized conditions to afford high to excellent yields of desired 2-amino-3-cyano-4H-pyrans by using a low loading of the CS-g-PAN nanocatalyst in EtOH as a green solvent. The CS-g-PAN heterogeneous catalyst can be reused at least for six runs while its catalytic activity does not reduce significantly. Among the advantages of this work are its clean reaction profile, short reaction times, high to excellent yields, and reusability and catalyst stability.

This study presents the synthesis of a new efficient purine-sulfonic acid ionic liquid immobilized onto magnetic nanosilica (SiO₂@Fe₃O₄@Purine-SO₃H). The synthesis of this nanocatalyst started by immobilizing purine onto magnetic nanosilica, followed by treatment with 1,3-propane sultone and subsequent acidification by H₂SO₄. The structure of the nanocatalyst was comprehensively characterized using FT-IR, TGA, SEM, VSM, XRD, BET, EDS, ICP and elemental analysis techniques. The catalytic activity of the introduced nanocatalyst was investigated in the synthesis of dihydropyrimidine derivatives, achieving high to excellent yields (75–94%) within 40 min at room temperature in ethanol, using only 20 mg of nanocatalyst. The results showed that the immobilized ionic liquid significantly enhanced the catalytic activity by increasing surface acidity and dispersion. This method offers a green, efficient, and reusable catalytic system for heterocyclic synthesis, featuring mild reaction conditions, a simple operational procedure, and facile nanocatalyst recovery.

A promising approach to improve the catalytic efficiency of metal–organic frameworks (MOFs) is their post-synthesis modification with ligands that have the potential to form stable complexes with metal species. Incorporation of the metal complex into the MOF structure results in a bimetallic catalytic system that exhibits better performance than the unmodified framework. The presented study synthesizes the pincer ligand using cheap and accessible cyanuric chloride and creatinine as the core and side arms, respectively, followed by reaction with Cu(OAc)₂ to yield the copper(II) complex. Then, it was used to modify the UiO-66-NH₂ framework via a covalent post-synthetic modification approach. The functionalized MOF was characterized by different techniques such as FTIR, FE-SEM, EDX, XRD, TGA, and N₂ adsorption–desorption. Using the advantage of synergistic effect between copper and zirconium, the modified MOF produced 1,4-dihydropyridine and 3,4-dihydropyrimidinone derivatives. Comparing the prepared catalyst with pristine UiO-66-NH₂ and bare copper(II) complex showed an enhanced catalytic activity of UiO-66-NH₂-CC@Cu(II) mainly due to the presence of complex. The proposed catalyst exhibited strong stability along with a recyclable performance, which are essential parameters for catalyst design in industry.

A straightforward ultrasound-assisted green multicomponent strategy was developed for synthesising benzo[h]pyrimido[4,5-b]quinoline-8,10(7H,9H)-dione derivatives. The protocol involves the condensation of 1-aminonaphthalene, barbituric acid, and various aromatic, aliphatic, and heterocyclic aldehydes under ultrasonic irradiation in aqueous ethanol as a benign solvent system. Ultrasound-promoted acoustic cavitation affords excellent yields, shorter reaction times, and high selectivity under mild, environmentally friendly conditions, in line with green chemistry principles. The synthesised derivatives were fully characterised by spectroscopic techniques. ADMET predictions indicated favourable pharmacokinetic properties. Molecular docking revealed strong binding affinities, particularly for compounds 4(e–o), with docking scores ranging from –7.05 to –9.80 kcal/mol against the progesterone receptor (PDB ID: 4OAR). Density functional theory (DFT) studies, including HOMO–LUMO analysis, provided valuable insights into the electronic structures and reactivity patterns of the molecules. Overall, this work demonstrates ultrasound-assisted multicomponent synthesis as a sustainable strategy for constructing bioactive heterocycles and suggests that the obtained derivatives hold potential for further development as anti-breast cancer agents.

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A series of hierarchical nanosheet-structured ZSM-5 zeolites were successfully synthesized via a dual-template synthesis strategy. The impacts of the material ratio in the gel include meso-/microporogen and Si/Al molar ratio, as well as the type of microporogen on the morphology of the hierarchical structure of zeolites, pore architecture, and acidic properties were systematic explored. Moreover, the relationship between the morphological changes and the arrangement of the template within the uncalcined zeolite was unveiled. The results indicated that the molar ratio of C_18-6-6Br (mesoporogen)/TPAOH exerted a remarkable influence on the morphology of zeolites. With the increase in the proportion of the C_18-6-6Br, the morphology of the zeolites shifted rapidly from massive to lamellar. Concomitantly, N₂ adsorption–desorption experiments show that both the specific surface area (ranging from 380 to 570 m²/g) and the external specific surface area (ranging from 188 to 382 m²/g) increased significantly. While the Si/Al ratio variations adjusted acid strength and quantity through crystallinity interplay, the type of microporogen influenced crystallization via electrostatic interactions and steric effects. Light olefins were produced by the catalytic cracking of waste cooking oil model compound in laboratory-scale fixed-bed reactors to evaluate the catalytic performance of these zeolites. The maximum light olefin yield (38.8%) could be obtained owing to the suitable acid amount and relatively large specific surface area of zeolite (500 m²/g). While meeting the yield requirements, it also achieved a relatively low coke deposition (23.54% coke content) through excellent diffusion performance.

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Having already been extensively studied due to containing two of the three most common heteroatoms, thiocarbohydrazone derivatives represent an intriguing class of compounds for many scientists. They have shown great biological activity as antioxidative, antimicrobial, and anticancer agents. In this paper, previous studies have been continued—from the series of monothiocarbohydrazones, asymmetrical bisubstituted derivatives were synthesized. Eighteen new bisthiocarbohydrazones were obtained and characterized. Purity and composition of synthesized compounds were determined with NMR (¹H, ¹³C) and FT-IR spectroscopy and elemental analysis. Six derivatives were successfully isolated in the form of single crystals, and X-ray analysis was applied. Intermolecular interactions were studied using multiple linear correlations based on LSER and LFER principles. In order to examine the antioxidative potential of new bisthiocarbohydrazones, the DPPH assay was used, and all compounds showed good activity. Derivatives with hydroxyl and methoxy groups, as well as those with a fluorine atom, proved to be the best antioxidant agents in this series of thiocarbohydrazones.

A novel dicationic Brønsted acidic ionic liquid (DBAIL) was synthesized via an acid–base reaction between 1-((3-dimethylammonium)propyl)pyridinium chloride and sulfuric acid. The obtained ionic liquid was thoroughly characterized by Fourier transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (¹H NMR) spectroscopy, carbon-13 nuclear magnetic resonance (¹³C NMR) spectroscopy, thermogravimetric analysis (TGA)/differential thermogravimetric analysis (DTG), mass spectrometry (MS), and the Hammett acidity function, thereby confirming its structural features and ionic properties. The DBAIL catalyzed the reaction of aldehydes, dimedone, and ammonium chloride at 110 (^{circ })C with 20 mol % of the DBAIL under solvent-free conditions, affording a series of 1,8-dioxodecahydroacridine derivatives with yields of up to 95 %. This synthetic method offers several advantages, including short reaction times, high yields along with low catalyst loading in neat conditions, and a simple work-up. Furthermore, the antibacterial activity of DBAIL was assessed against a panel of pathogenic microorganisms, revealing strong antimicrobial effects against both Gram-positive and Gram-negative bacteria, while no activity was observed against Candida albicans. These results underscore the potential of the DBAIL for applications in both synthetic chemistry and biomedicine. Finally, the in vitro cytotoxicity of the DBAIL was evaluated by MTT assay.

Lignin quantum carbon dots (CQDs) were prepared using basic lignin as the carbon source. They were loaded onto Z-type ZnIn₂S₄/WO₃ heterojunction semiconductor materials by a one-step hydrothermal method to construct a ternary composite photocatalyst. Taking the photocatalytic water hydrogen evolution reaction performance as an indicator, it was found that the 33% CQDs/ZnIn₂S₄/WO₃ composite photocatalyst exhibited the highest hydrogen evolution reaction rate of 15.355 mmol·h⁻¹·g⁻¹, which was twice as high as that of ZnIn₂S₄/WO₃ (7.522 mmol·h⁻¹·g⁻¹). This study successfully constructed CQDs/ZnIn₂S₄/WO₃ tenary heterojunction photocatalyst with excellent and stable hydrogen production performance, which fully demonstrated the feasibility of loading lignin-based CQDs to enhance the photocatalytic performance of ZnIn₂S₄ for high-value utilization of lignin.