Journal of Chemical Sciences最新文献

A new copper (II) coordination polymer [{Cu(TMDP)(2,3-pydc)}.2H₂O]_n (A) has been synthesized successfully by solvolysis method using ligands 4,4′-trimethylenedipyridine (TMDP) and 2,3-pyridinedicarboxylic acid (2,3-pydc). The structure of the synthesised coordination polymer is confirmed by the single crystal X-ray diffraction study and also supported by CHN analysis. FTIR, UV-visible spectroscopy, thermogravimetric analysis (TGA) and powder XRD study are used to characterize A. The polymer in aqueous solution is applied as effective catalyst for reductive degradation of methyl orange (MO) and Congo red (CR) dyes with reducing agent sodium borohydride (NaBH₄) under dark. The detail study of the catalytic reaction and its kinetic study reveals 97% and 76% degradation of MO and CR with rate constants of 0.061 min⁻¹ and 0.005 min⁻¹, respectively. This is the first example where a coordination polymer has been used for reductive degradation of dyes under dark condition.

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A newly synthesized copper (II) coordination polymer [{Cu(TMDP)(2,3-pydc)}.2H₂O]_n (A) has been developed and studied by different analytical methods. The polymer (A) is then used as catalyst for degradation of anionic (MO and CR) dyes.

Nowadays, microfluidic synthesis has many advantages over bulk synthesis. By controlling the flow into the microfluidic chip, we can synthesize nanoparticles with defined and precise characteristics. A continuous microfluidics synthesis of CaWO₄ was conducted to obtain nanoparticles with a Scheelite structure approximately 10 nm in diameter. The CaWO₄ nanoparticles were characterized using elemental composition, chemical structure, particle size distribution, and morphology. Calcium tungstate and its derivatives are well known for their optical properties and have great potential for medical applications. The small diameter of nanoparticles allows the synthesis of composites on their basic for theranostics in cancer treatment. Our work indicates the potential opportunity of a continuous microfluidics technique for the rapid fabrication of Scheelite-type tungstate.

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Microfluidic synthesis of CaWO₄ nanoparticles with a Scheelite structure using a continuous process yielding 10 nm particles. Characterization includes elemental composition, structure, and morphology. This substance has potential applications in photodynamic therapy because of its optical properties.

A method for synthesizing 3-substituted isocoumarins under copper catalysis involves the cyclization reaction of o-bromobenzoic acid and alkynes in DMSO, with the assistance of K₂CO₃ at 100 °C. It exhibits a wide range of substrate compatibility and excellent tolerance towards diverse functional groups.

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A method for synthesizing 3-substituted isocoumarins under copper catalysis involves the cyclization reaction of o-bromobenzoic acid and alkynes in DMSO, with the assistance of K₂CO₃ at 100 °C. This reaction demonstrates a synthesis yield of 8–81% for 3-substituted isocoumarins.

Investigating alternative energy sources is now crucial since the topic of climate action is growing in significance. One of the most promising renewable biomass feedstocks is levulinic acid (LA), which can be converted via an intermediary called γ-valerolactone (GVL) into value-added products. This study examined the hydrogenation of levulinic acid to γ-valerolactone using various copper-supported H–ZSM-5 catalysts with different Cu loadings (2–30 wt%) that were synthesized using a simple impregnation technique. The synthesized catalyst's morphological and chemical structure was examined using a variety of techniques, including XRD, N₂ adsorption-desorption, TPR, TPD–NH₃, and N₂O titration. Overall, at 265°C and 30 hours of time on stream (TOS), 5 Cu/H–ZSM-5 showed the best conversion (87%) and selectivity (83%).

Graphical Abstract

One of the most promising renewable biomass feedstocks is levulinic acid (LA), which can be converted via an intermediary called γ-valerolactone (GVL) into value-added products. This study examined the hydrogenation of levulinic acid to γ-valerolactone using copper-supported H–ZSM-5 catalysts with different Cu loadings.

Novel (E)-3-(dimethylamino)-1-(quinolin-3-yl)prop-2-en-1-one and (E)-3-(dimethylamino)-1-(quinolin-3-yl)but-2-en-1-one (2) were synthesized in excellent yields by reacting 3-acetylquinoline with DMF-DMA and DMA-DMA respectively. Subsequently, 2 were used as the precursors for the synthesis of 3-(pyrazolo[1,5-a]pyrimidin-7-yl)quinolines and 3-(5-methylpyrazolo[1,5-a]pyrimidin-7-yl)quinolines (4). All the synthesized compounds were subjected to structure elucidation and evaluated for their antiparasitic potential with special reference to their anti-malarial properties. The in-vitro studies of the synthesized compounds revealed moderate anti-malarial efficacy for compounds 4b, 4c, 4d, 4k, 4l and 4m. Compounds 4g and 4i showed highest activity displaying IC₅₀ values of 2.10 and 2.77 (mu)M, respectively, for the chloroquine-sensitive strain of P. falciparum, and 4.26 and 2.87 (mu)M, respectively, for the chloroquine-resistant strain. The in-vitro cytotoxicity of the compounds showed CC₅₀ as >500 µM and thus, found to be safe. Molecular docking of the novel series of ligand 4a–4n against the target protein P. falciparum PfLDH enzyme target (PDB ID 1LDG) revealed good binding energies ranging from –8.06 to –11.02 kcal/mol with low inhibition constants summed up as 1.04, 473.55, 352.51, 290.9, 437.86, 1.23, 41.18, 26.81, 162.76, 300.38, 70.2, 29.84, 4.14, 8.4 µM, respectively. The lower the inhibition constant (µM), the greater is the binding affinity and lower the medication required to inhibit the activity of the target receptor.

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(E)-3-(dimethylamino)-1-(quinolin-3-yl)but-2-en-1-one with 3-aminopyrazole under ultrasonic irradiation in aqueous medium yielded novel 3-(pyrazolo[1,5-a]pyrimidin-7-yl)quinolines and 3-(5-methylpyrazolo[1,5-a]pyrimidin-7-yl)quinolines. Antimalarial studies against Pf3D7 strain resulted in moderate activity with compound 4g showing highest activity. Molecular docking analysis of the compounds reveals the potentiality of the series to serve as antimalarial agents against CQ-sensitive (Pf3D7) and multi-drug-resistant (PfK1).

Readily available, naturally derived lignin was transformed into a Brønsted acidic organocatalyst. The obtained catalyst was utilized in the environmentally benign synthesis of biologically relevant indole derivatives such as vibrindole, turbomycin, etc. The scope of the developed methodology was further extended for the synthesis of aniline-tethered indoles, 4H-chromene, and indolin-2-one derivatives. Further, vicinal difunctionalization was successfully carried out with the aid of the developed organocatalyst. Imperatively, all the aforementioned reactions were carried out in the aqueous medium. The reusability of the heterogeneous catalyst was also proved by carrying out the reaction with the recovered catalyst.

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Lignin-based naturally derived Brønsted acidic organocatalyst was utilized in the environmentally benign synthesis of biologically relevant indole derivatives, 4H-chromene, and indolin-2-one derivatives. All the aforementioned transformations were carried out in an environmentally benign aqueous medium.

This study reports a hydrotropic activity for synthesizing 1H-pyrazolo[1,2-b]phthalazine-5,10-dione through one pot four component aldehyde condensation, malononitrile, phthalic anhydride, and hydrazine hydrate. The simple and green hydrotropic synthetic approach offers numerous advantages such as non-toxic, inexpensive, mild reaction conditions, avoidance of harmful solvents, shorter reaction time, an excellent yield of products, simple workup, Chromatography-free, and eco-friendly. ¹H-NMR confirmed all the synthesized compounds.

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Quantum chemistry provides valuable insights into the structure and reactivity of heterocyclic organic compounds, facilitating the rational design of novel molecules with targeted functionalities. In this paper, structural features and chemical properties of 2-(2-phenyl-1,3-benzoxazol-7-yl)benzaldehyde, a benzoxazole-based heterocycle, were investigated. This multifaceted study combines crystallographic and quantum chemical methods to elucidate molecular geometry, crystal packing, and chemical reactivity of mono and dimeric forms. A rich network of intermolecular interactions, including nonclassical hydrogen bonds (C–H···O and C–H···N), π-stacking, and a unique C=O···π(ring) interaction, were found to govern the solid-state structure. Multi-approach quantum mechanics analysis using dispersion-corrected DFT (ωB97X-D/aug-cc-pVTZ) revealed the electronic features, energetics, and nature of these interactions. Furthermore, Conceptual DFT identified the molecule as a moderate electrophile and strong nucleophile in polar organic reactions, while Parr functions pinpointed favourable sites for electrophilic and nucleophilic attacks.

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Quantum chemistry provides valuable insights into the structure and reactivity of heterocyclic organic compounds, facilitating the rational design of novel molecules with targeted functionalities. In this paper, a benzoxazole-based heterocycle was computationally investigated using dispersion-corrected density functional theory. The focus was on noncovalent interactions and chemical reactivity in both mono and dimeric forms. This work not only introduces the molecule for future study, but also emphasizes the capability of used theoretical approaches in elucidating structure and reactivity within heterocyclic compounds.