Research on Chemical Intermediates最新文献

A novel composite material, consisting of carbon quantum dots and magnesium oxide, has been successfully synthesized to effectively stabilization of copper nanoparticles. The characterization of the Cu@CQD@MgO nanocomposite was conducted through a variety of analytical techniques, including FT-IR, SEM, EDS-SEM, TEM, EDX, and ICP analyses. This innovative material has demonstrated remarkable catalytic performance in the synthesis of pyran derivatives, achieving yields between 82 and 97% within 5–20 min, as well as in the production of 1,2,3-triazole derivatives, with yields ranging from 85 to 97% over 15–20 min. The method offers numerous benefits, such as conducting reactions under mild conditions, achieving high yields, and utilizing environmentally friendly solvents like a 1:1 mixture of water and ethanol at room temperature. Collectively, these advantages enhance the efficiency, reliability, and practicality of the synthetic approach outlined in the study, highlighting the potential of Cu@CQD@MgO as a versatile and effective catalyst for organic transformations. Furthermore, the capability to reuse the Cu@CQD@MgO nano catalyst for six consecutive cycles underscores its sustainability and cost-effectiveness, positioning it as a promising choice for large-scale production or continuous processing.

The drug discovery process involves the development of strategies to provide privileged small molecules and allowing access to new potential therapeutic entities. In this work, an efficient process to access chromeno-pyrazolo[1,2-b]phthalazines and indazolo[1,2-b]phthalazines via the three-component reaction between 2,3-dihydrophthalazine-1,4-dione, aromatic aldehydes and 4-hydroxycoumarine/dimedone is described. The notable features of this method include a much milder procedure, a shorter reaction time, a wide range of functional group tolerance, and absence of any tedious workup or purification. This procedure avoids hazardous reagents/solvents and is thus an eco-friendly alternative to the existing methods. Synthesized compounds also evaluated for in silico based pharmacophore investigation to check plausible therapeutic potential. Importantly, the synthesized molecules were found to bind at the active site catalytic cleft of c-Jun N-terminal kinase (JNK3), a well-established anti-neurodegenerative drug target and also plays crucial role in cancer, obesity and diabetic conditions. Higher free energy of binding (− 11.70– − 8.20 kcal/mol)) of the synthesized molecules with JNK3 than previously known JNK3 inhibitor J6F (− 6.5 kcal/mol) suggest sturdy ligand binding. Moreover, binding stability is corroborated by all atomistic molecular dynamics simulation performed in physiologically simulated conditions as well as deep learning-based binding affinity (pK_d) predictions. The therapeutic potentials of the synthesized molecules have been postulated through the detailed structure function analysis and its interaction with their cognate physiological target. DFT investigations also studied for all the synthesized chromeno-pyrazolo[1,2-b]phthalazines and indazolo[1,2-b]phthalazines.

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The epoxidation of olefins is a pivotal reaction in organic synthesis, yielding epoxides that serve as essential intermediates in the production of pharmaceuticals, polymers, and fine chemicals. Conventional epoxidation methods often employ hazardous oxidants and nonrecyclable catalysts, leading to significant environmental and economic drawbacks. This study presents a novel, eco-friendly approach for the aerobic epoxidation of olefins utilizing recyclable NiFe₂O₄@SO₃H@AC magnetic nanoparticles. The catalyst comprises nickel ferrite (NiFe₂O₄) for magnetic separability, sulfonic acid groups (SO₃H) to provide acidic catalytic sites, and activated carbon (AC) to enhance surface area and adsorption properties. Employing molecular oxygen as the terminal oxidant, this system offers a sustainable alternative to traditional methods. The NiFe₂O₄@SO₃H@AC catalyst demonstrates high activity and selectivity across a range of olefins, with excellent recyclability, maintaining performance over multiple reaction cycles. Characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FT-IR), confirm the structural integrity and functionality of the catalyst. This work advances the field of green catalysis by providing an efficient, recyclable, and environmentally benign method for olefin epoxidation, addressing critical challenges in sustainability and industrial applicability, and instilling confidence in its reliability.

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In this study, a friendly synthesis route for Mg–Al mixed metal oxide catalysts was successfully developed using the one-pot ball milling method, which was then applied to cyclohexanone self-condensation. This solvent-free solid-phase preparation, driven by mechanical force, rapidly fabricates the mixed metal oxide crystalline phase. Unlike the traditional hydrothermal co-precipitation method, it eliminates the need for solvent separation and recycling, reducing preparation time from hours to just 30 min. Consequently, it is both environmentally friendly and efficient. The structure and performance of the catalyst were analyzed using various techniques. Results indicate that it has a higher active sites density and is effective in cyclohexanone condensation reactions. The mean temperature method (MTM) was also proposed to analyze the temperature fluctuations during the ball milling process, which more accurately reveals the impact of temperature variations on the reaction. The results demonstrate that the ball milling method has a low apparent activation energy (Ea, app = 46.25 kJ/mol), indicating its superiority in catalytic reactions.

The present work describes the simple, general and efficient one-pot synthesis of chromeno [4, 3-b] chromene (4a–4t) and tetrahydrodipyrazolopyridine (8a–8q) derivatives catalyzed by a deep eutectic solvent named ETPP-Br/THF-TCA-DES (ethyl triphenylphosphonium bromide and tetrahydrofuran-2, 3, 4, 5-tetracarboxylic acid). Here, a diverse set of above derivatives were produced with high yields in short times by converging a set of green chemistry metrics in the implementation of multicomponent reactions including the use of low amounts of catalyst (10–15 mg), the absence of the need for harsh temperature conditions, using water as a benign medium and ideal values of environmental factor (E-factor), process mass intensity (PMI) and atom economy (AE). These advantages, along with the introduction and characterization of novel derivatives to the literature, the easy recyclability of DES and its repeated use with a slight decrease in catalytic activity (six times), emphasize the novel aspects of our method as a significant contribution to the advancement of green methods.

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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.