Research on Chemical Intermediates最新文献

In this work, a novel ultrasound mediated synthesis of chromone based α-aminophosphonate using CdS/CNT nanocomposite has been reported. The nanocomposite was characterized using techniques like Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction, Raman spectroscopy, Brunauer–Emmett–Teller (BET) analysis, and morphology studies were carried out using Field-Emission Scanning Electron Microscopy, and Transmission Electron Microscopy. Further, the synthesized α-aminophosphonate derivatives were characterized using FTIR, ¹H-NMR and CHN elemental analysis. The present method provides various advantages such as operational simplicity, high yield, short reaction time, easy workup and solvent free condition. In addition, the catalyst exhibited remarkable reusability, demonstrating consistent performance up to five runs without any significant loss of its catalytic activity. The ICP-AES analysis suggested that there is no leaching of CdS from the surface of CNT.

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The researchers of this study synthesized a new magnetic solid acid catalyst by processing Fe₃O₄ with glycine, pyrrole-2-carbaldehyde, and sulfuric acid as an acid group via a simple method. Its chemical structure was determined through a variety of analyses, including Fourier transform infrared spectroscopy, vibrating sample magnetometer, thermal gravimetric/derivative thermal gravimetric, field emission scanning electron microscope, energy-dispersive X-ray spectroscopy (EDX), EDX-mapping, transmission electron microscopy, inductively coupled plasma, X-ray diffraction, and Brunauer–Emmett–Teller. Following this, this efficient strong solid acid catalyst was used for the synthesis of of 2-amino-3-cyano-4H-pyran and polyhydroquinoline derivatives (84–95% yield in 5–30 min and 88–96% in 5–15 min, respectively). The nano-catalyst could be easily separated from the reaction mixture using a permanent magnet and utilized up to five times without experiencing any significant decrease in its catalytic activity. The implementation of this method offers several benefits including effortless separation, excellent catalytic activity, environmentally friendly reaction conditions, relatively high product yield, and low cost. Moreover, the recent research has demonstrated the notable antiviral effects of certain pyran and quinoline derivatives against COVID-19.

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1,3-Dithiocyanatoacetone was prepared by reaction of 1,3-dichloroacetone with potassium thiocyanate in ethanol in almost quantitative yield. In contrast to the NMR spectra recorded in acetone-d₆, NMR spectra of 1,3-dithiocyanatoacetone in DMSO-d₆ solution revealed the presence of the enol form. The keto-enol tautomerism is discussed and the structure of main conformers and tautomers of dithiocyanatoacetone and its acid hydrolysis product, S-[(2-oxo-2,3-dihydro- 1,3-thiazol-4-yl)methyl]thiocarbamate, was investigated by quantum chemical methods. The vibrational spectra were calculated and found to be in a good agreement with the experimental FT-IR spectra. The structure of 1,3-dithiocyanatoacetone and S-[(2-oxo-2,3-dihydro-1,3-thiazol-4-yl)methyl]thiocarbamate was studied by X-ray diffraction analysis. Molecular docking and bioavailability parameters calculations showed the potential of the compounds as carbonic anhydrase inhibitors.

This study reported the synthesis of well-dispersed palladium nanoparticles (PdNPs) using microwaves. Additionally, this method is quick, cheap, chemical-free, and environmentally friendly. The Eupatorium adenophorum aqueous extract, which contains polysaccharides and other phytochemicals, effectively reduced and stabilized PdNPs. We have preliminarily confirmed that PdNPs form via UV–visible spectroscopy and proposed a mechanism of PdNPs formation via Fourier transform infrared spectroscopy. EA-PdNPs have a face-centred cubic structure, as confirmed by XRD analysis. The images obtained by transmission electron microscopy showed spherical PdNPs whose average size was 11 ± 2 nm. EA-PdNPs showed good catalytic activity towards the reduction of methylene blue (MB), congo red (CR) dyes, and 4-nitrophenol (4-NP). It was found that EA-PdNPs showed a reduction efficiency of 94% against MB, CR, and 4-NP dyes even after five cycles. EA-PdNPs are anticipated to contribute to environmental water remediation significantly.

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Schematic representation of the synthesis of EA-PdNPs and their catalytic applications

We prepared Co@O-gCN as a means of activating peroxomonosulfate (PMS) to remove acid orange 7 (AO7). The effects of a series of considerations including catalyst amount, PMS dosage, pH and temperature on the degradation of AO7 were evaluated, and we discovered that the time needed to remove AO7 completely decreased as pH increased, and as the pH was adjusted to 11, the addition of 10 mg Co@O-gCN and 375 mg/L PMS resulted in the complete removal of 20 mg/L of AO7 within 10 min. The effects of coexisting anions and the actual water matrix in the process of removing AO7 by the Co@O-gCN /PMS system were investigated. Electron paramagnetic resonance (EPR) and quenching experiments revealed that under acidic as well as neutral conditions, Co (IV) was the main reactive species, whereas under alkaline conditions, the main reactive species changed to superoxide radicals (O₂^·−), followed by monoclinic oxygen (¹O₂).

Shrimp head by-product (SHP) has been increasingly studied for applications in bacterial fermentation and the production of secondary metabolites. In this work study, Bacillus velezensis EB.KN15 was grown via fermentation using SHP as a novel substrate on a large scale and its potential fungicidal effect against durian pathogen fungi was evaluated. SHP was found rich in protein content (29.18%) and several mineral elements suitable for EB.KN15 fermentation. The appropriate cultural medium for B. velezensis EB.KN15 growth in the small-scale fermentation using 250 mL-Erlenmeyer flask included 2% SHP/LB (7/3), 0.05% MnSO₄, and 0.1% KH₂PO₄ at 34 °C, pH 7 for 36 h. When scaling up fermentation in a 14 L-bioreactor system, this strain exhibited better productivity (1.2 × 10¹² CFU/mL) in a shorter fermentation time (only 10 h). Anti-fungal activity tests revealed for the first time, that EB.KN15 has potential fungicidal effect against Fusarium incarnatum, Phytophthora palmivora, and Fusarium solani with high inhibition values of 70%, 78.95%, and 80%, respectively. Gas chromatography mass spectrometry could identify 11 major volatiles produced by B. velezensis EB.KN15 in the supernatant. The molecular docking indicated effective interaction of these major volatiles with the target protein responsible for F. solani inhibition with good binding energy (DS ≤ 7.1 kcal/mol) and an acceptable root-mean-square deviation value (1.05–1.96 Å). This study suggests that SHP is a new substrate for the fermentation of B. velezensis EB.KN15 and recorded this strain as a novel potential candidate to effectively manage durian pathogen fungi.

Water pollution has always been an inescapable challenge in the development of human society. Photocatalytic technology is regarded as a promising strategy for water pollution control. In this work, a novel Cu₂O/TiO₂@Ti₃C₂T_x MXene photocatalyst is constructed to create diverse electron transport pathways, thereby promoting charge separation and achieving superior photocatalytic performance. The synergistic effects of composite photocatalytic materials are instrumental in degrading organic dyes under visible light. The successful construction of a heterojunction structure between Cu₂O and in situ generated TiO₂ mitigates charge recombination post-separation, significantly extending the lifetime of photogenerated carriers. Additionally, the incorporation of Ti₃C₂T_x serves as an effective conductive medium, facilitating the separation and transfer of photogenerated charges within the material. Therefore, the Cu₂O/TiO₂@Ti₃C₂T_x MXene composites exhibit exceptional photocatalytic activity, showcasing the best performance, achieving a degradation rate of 71.5% after 3 h of visible light irradiation. These findings underscore the potential of this new compound in enhancing photocatalytic organic degradation, highlighting the promising application prospects of photocatalytic materials.

In this study, Fe–Mn/activated carbon (AC) catalysts were prepared to investigate the CO + NH₃ coupling for deducing the NO removal mechanism by iron and manganese supported on AC catalysts under moderate to low-moderate aerobic conditions. Through the catalyst surface morphology, phase analysis, and other test results, we propose a mechanism for the CO + NH₃ coupling that results in NO removal at medium to low temperatures. The results indicate that NO conversion initially decreases and then increases in the range of 150–300 °C with 9% oxygen content. The NO conversion of the 3.5Fe–7.0Mn/AC catalyst reached 95%, surpassing other catalysts, with an inflection point near 230 °C. Characterization of the 3.5Fe–7.0Mn/AC catalyst revealed a smooth surface, uniform pore development, a high number of micro and medium pores, and elevated surface oxygen species (O_α) content. Mn₂O₃ and Fe₃O₄ are uniformly distributed on the surface, enhancing the reaction gas contact area and thereby improving NO conversion. Fe²⁺ is identified as the primary active site for NO removal. Increased Mn loading raises the Fe²⁺ and Mn³⁺ levels, with Mn³⁺ improving the NO conversion rate.

Heterostructures of CuFe₂O₄@NH₂-MIL-88B (Fe) were effectively synthesized and utilized as an effective catalyst under visible light and oxidation conditions for the synthesis of quinazolinones. At room temperature, good to excellent yields of the desired products were obtained. In addition, the composite heterostructures that were created showed a higher level of photocatalytic activity when exposed to visible light compared to both CuFe₂O₄ and NH₂-MIL-88B (Fe) individually. In comparison with CuFe₂O₄ and MIL-88B (Fe), the absorption peak of CuFe₂O₄/MIL has increased. Increasing visible light absorption could lead to an increase in electron–hole pair formation, which would improve photocatalytic activity. Furthermore, the incorporation of CuFe₂O₄ to the NH₂-MIL 88B (Fe) surface results in a significant reduction in photoluminescence emission intensity. Moreover, from the perspective of sustainable chemistry, CuFe₂O₄@NH₂-MIL-88B (Fe) demonstrated good recyclability, being recycled six times with little to no loss in catalytic efficacy.

Mesoporous carbon nitride (MCN-K) was prepared using mesoporous KIT-6 material as a template and ethylenediamine and carbon tetrachloride as N and C sources, respectively. The synthesized MCN-K was treated with sulfuric acid under different experimental conditions, thus obtaining sulfonated MCN-KS adsorbents. The effects of initial solution pH, initial dye concentration, adsorbent amount, and temperature on Rhodamine-B (Rh-B) dye removal were investigated. The XRD, FT-IR, and N₂ adsorption–desorption analyses confirmed that the mesoporous carbon nitride structure was successfully synthesized. The high nitrogen content (C/N molar ratio: 4.0) of the MCN-K sample was confirmed by (carbon, hydrogen, nitrogen and sulfur) CHNS elemental analysis. The XPS analysis was used to characterize the chemical states of the C, N and S atoms in the MCN-K and MCN-KS sorbents. It was found that there was not much difference between the removal percentages (93.13–89.92%) obtained in the pH range (4–12) studied. This result was attributed to the zwitter-ion form of Rh-B. The exothermic nature of the adsorption process of Rh-B on the MCN-K sorbent was determined by adsorption experiments performed at different temperatures. Adsorption capacities obtained from the Langmuir model were 185.2–104.2 mg/g in the studied temperature range. The kinetic behavior of the adsorption process was explained by the pseudo-second-order kinetic model in terms of both correlation coefficients (R² > 0.91) and q_e (35.59–190.26 mg/g) values. When the percentages of dye removal of the un-sulfonated and sulfonated samples were compared, it was found that sulfonation increased the adsorption rate considerably but did not contribute positively to the dye removal percentage.