Research on Chemical Intermediates最新文献

Infectious diseases, induced by various pathogenic microorganisms, can enter the body and disrupt normal physiological functions, leading to a range of symptoms and health complications. So, to ascertain a significant anti-infectious agent against antimalarial and anti-tuberculosis ailments, the previously synthesized and extensively characterized (mass spectrometry, NMR (¹H and ¹³C), electronic spectra, infrared, magnetic moment, ESR, molar conductance, powder XRD, SEM and EDAX) Schiff base ligands (1–4) and their octahedral Co(II), Ni(II), Cu(II), Zn(II) complexes (5–20) were studied. The biological evaluation demonstrated that compounds (1, 5–8) and (3, 13–16) showed high potency against malaria and tuberculosis, respectively. Furthermore, Zn(II) complexes (8) and (16) exhibited the greatest efficacy, with IC₅₀ value of 0.32 ± 0.06 µM and MIC value of 0.0081 µmol/mL. Moreover, molecular docking investigation against the 1U5A, 8E1Z proteins for malaria and 5V3Y, 3PTY proteins for TB, along with ADMET investigations, was conducted on highly active compounds (1, 3, 5–8, 13–16) to validate their biological findings. The theoretical analysis also supported the superior efficacy of (8) and (16) complexes, demonstrating their lowest binding affinity (1U5A (− 8.1 kcal/mol), 8E1Z (− 8.9 kcal/mol), 5V3Y (− 10.1 kcal/mol), 3PTY (− 10.2 kcal/mol)), favorable coordination modes and drug likeness property.

Twelve homoleptic Cu(I) complexes with triazine-type ligands were designed and analyzed theoretically for their possible application in dye-sensitized solar cells (DSSC). This research analyzed the effect of π-conjugation and substitution of different anchoring groups in the triazine ligands. The molecular structures of the compounds were obtained through density functional theory (DFT). A relationship between complex geometry distortion (τ₄) and optoelectronic properties was found. UV–Vis absorption spectra and electronic transitions were studied using time dependent-density functional theory (TD-DFT). The complexes presented absorption bands in the 300–655 nm range, attributed to metal → ligand and ligand-to-ligand transfer. Energy levels of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) meet the requirements to consider molecular proposals as sensitizers. Chemical reactivity parameters of interest were obtained and analyzed, such as chemical hardness (η), electron-donating power (ω⁻), electron-accepting power (ω⁺), and electrophilicity index (ω). For all Cu(I) complexes, a relation was found between chemical hardness and τ₄ values. The free energy electron injection (ΔG_Inject) and light harvesting efficiency (LHE) were determined and discussed. All previous studies indicate that all complexes present interesting properties like dyes in DSSC applications.

The utilization of visible light irradiation in organic synthesis has garnered significant attention due to its environmentally friendly nature and efficiency. In this study, we explore the application of graphitic carbon nitride (g-C₃N₄) as a photocatalyst for the synthesis of 2-Arylbenzothiazole under visible light irradiation. The reaction conditions were optimized to achieve high yields (89–97%) and selectivity of products. Characterization techniques such as FTIR spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and UV–Vis Diffuse Reflectance Spectra (DRS) were employed to analyze the catalyst structure. The results demonstrated that g-C₃N₄ acted as an effective photocatalyst, facilitating the synthesis of benzothiazole with excellent yields (89–97%). This approach marks a notable improvement over prior methodologies, leading to significantly faster reaction times and improved yields. Additionally, the exceptional recyclability of g-C₃N₄ allows it to be reused in multiple reaction cycles without significant loss of activity, which is a crucial factor in reducing waste and resource consumption, facilitating a greener process. Consequently, it highlights g-C₃N₄’s potential for sustainable and eco-friendly synthesis of 2-Arylbenzothiazole and other valuable organic compounds.

Graphical abstract

• The g-C₃N₄ was synthesized by thermal polymerization of urea, and was characterized through several technique such as XRD, FTIR, SEM, and DRS.

• g-C₃N₄ was used as highly efficient photocatalyst of 2-arylbenzothiazole under visible light irradiation.

• Benzothiazoles were successfully prepared, yielding 89–97% in a brief stirring time of 5–15 min.

• g-C₃N₄ continued to exhibit high catalytic activity after being recycled multiple times, without any significant degradation.

The current research work highlighted the bio-fabrication of tin oxide nanoparticles (SnO₂ NPs) by employing Phyllanthus emblica leaf extract. These investigations concentrated on the physiochemical characteristics of the developed material and examined their effectiveness as photocatalysts and antibacterial agents. The structural characteristics of the bio-fabricated SnO₂NPs were investigated by XRD, SEM, FTIR, and UV spectroscopic techniques. Photocatalytic efficacy of the constructed materials was evaluated in the removal of the 2,4 dicholorophenoxy acetic acid (2,4 D); meanwhile, the antibacterial potency of the developed material was assessed against the chosen bacterial strain Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, and Streptococcus pyogenes. The XRD and SEM examination revealed that the particles are spherical with diameters ranging from 50 to 60 nm. Subsequently, the developed SnO₂ NPs demonstrated significant photocatalytic potency in the removal of the 2,4 D from the aqueous solution, and approximately 74% of organic pollutants were removed from the aqueous solution within the period of 120 min. The antibacterial assay demonstrated that the developed material shows significant inhibition of the tested bacterial strain. Maximum inhibition was observed against the Klebsiella pneumoniae with the 21 mm zone of inhibition at 60 µg/mL.

In order to photocatalytic degradation of ethylene in environmental pollution, TiO₂ (B) featuring a multiphase crystal structure was first synthesized via hydrothermal synthesis method. The efficiency of photocatalytic degradation of ethylene and methyl orange by TiO₂ (B) was up to 49.23% and 60%, respectively, and the specific surface area of TiO₂ (B) was as large as 277.69 m²/g. Subsequently, photocatalytic films loaded with the TiO₂ (B) were produced using an extrusion casting machine coupled with a twin-screw extruder. The mechanical properties and barrier property to oxygen were enhanced by adding 1% TiO₂ (B) to photocatalytic films. The hydrophilicity of the photocatalytic films and the decrease in contact angle confirmed the existence of the ‘Honda-Fujishima effect’. The highest degradation efficiency of methyl orange and ethylene by the photocatalytic film could reach 9% and 7.79%, respectively. Both TiO₂ (B) and photocatalytic films showed good antibacterial properties against Escherichia coli and Staphylococcus aureus. TiO₂ (B) and photocatalytic films have been shown to have excellent photocatalytic degradation performance of organic compounds.

The synthesis of ethyl (hetero)arylidene cyanoacetates, valuable intermediates in organic chemistry, has been investigated using several commercially available and synthetic nitrogen-based organocatalysts. 4,4′-Trimethylenedipiperidine (TMDP) was chosen as an efficient organocatalyst regarding short reaction times, excellent yield with a conversion of 100%, and high selectivity. The pure products could be isolated and devoid of a costly workup. The residue could be directly reused for the next catalytic run. Encouragingly, TMDP exhibited chemical stability and high recyclability in five subsequent runs without a significant loss in catalytic activity. Scale-up experiments also demonstrate the current strategy’s promising industrial application. Mechanistic studies were conducted to provide insights into the reaction pathways and possible interaction/reaction between organocatalyst and each reactant through performing control experiments and studying FTIR in neat state and NMR spectra in aprotic and protic deuterated solvents. The developed metal-free and halogen-free catalytic strategy offers cost-effectiveness, low toxicity, and enhanced sustainability.

Graphical Abstract

The rapid increase in antibiotic contaminants such as Tetracycline (TC) in aquatic environments poses significant threats to human health and ecosystems. This study presents a novel Mn-Al layered double hydroxide (LDH) composite with rice husk biochar (RHBC) as a highly efficient visible light photocatalyst for the degradation of TC in wastewater. The Mn-Al-LDH/RHBC composite was synthesized via a simple co-precipitation method and characterized by UV–vis DRS, PL, TRPL, EIS, and TPR tests, confirming its wide visible spectral absorption, low electron–hole recombination rate, and high charge transfer efficiency. Photocatalytic performance tests showed that Mn-Al-LDH/RHBC achieved a 90.10% TC degradation efficiency within 90 min of irradiation. Mechanistic studies using EPR and DFT analysis identified ·OH and ·O₂⁻ as the primary reactive species in TC degradation. Additionally, QSAR analysis demonstrated a reduction in the biotoxicity of TC and its intermediates post-degradation. This work offers a new insight for the utilization of biomass waste and the improvement of Mn-Al-LDH/RHBC photocatalytic performance, and extends the broad potential application of biochar-based photocatalyst in antibiotic-contaminated wastewater treatment applications.

CuO, WO₃ and CuO/WO₃ composite catalysts were synthesized by using a sol–gel technique. The as-prepared catalyst nanoparticles were characterized by using FTIR, XRD, FESEM, fluorescence spectroscopy and UV–Vis absorbance spectroscopy. FTIR and XRD analyzes showed that CuO and WO₃ nanoparticles were successfully synthesized. FESEM images revealed homogeneous distribution of composite components within each other. The optical band gap of WO₃ was narrowed with the inclusion of CuO. The sonocatalytic activity of the as-prepared samples was studied by sonocatalytic degradation of an organic dye, methylene blue, under ultrasonic irradiation. The effect of catalyst loading and radical scavenger on the dye degradation rate was also examined. All composite samples exhibited higher sonocatalytic activity than pure samples. The highest sonocatalytic dye degradation efficiency (52.7%) was obtained with the CuO/WO₃ composite at a 2/1 mol ratio. After five cycle experiments, the sonocatalytic dye degradation efficiency of the CuO/WO₃ composite decreased slightly to 36.7%.