Mesoporous silica and organosilica nanoparticles supported chiral diol catalysts were prepared and tested in the reaction of Ti-promoted enantioselective diethylzinc addition to aromatic aldehydes. C ₂ -BSi-MON-(a) with the largest pore width stood out as the most effective catalyst (99% conversion).

In this study, heterogenization of C ₂ -symmetric (1R,2R)-1,2-bis(4-(3-(triethoxysilyl)propyl)phenyl)ethane-1,2-diol compound and investigation of the effect of structural arrangements of nanocatalysts on catalytic activity were carried out. For this, bissilyl derivative of (1R,2R)-1,2-bis(4′-bromophenyl)-ethane-1,2-diol, named as C ₂ -BSi, was obtained by 2-step synthesis. Then, mesoporous silica nanocatalysts C ₂ -BSi@SBA-15 and C ₂ -BSi@MCM-41 were synthesized by grafting of C ₂ -BSi onto SBA-15 and MCM-41, whereas mesoporous organosilica nanocatalysts C ₂ -BSi-MON-(a) and C ₂ -BSi-MON-(b) were synthesized by co-condenzation of C ₂ -BSi and tetraethyl orthosilicate (TEOS). Structure determinations of synthesized organic substances were performed by ¹H, ¹³C NMR, Fourier transform infrared (FT-IR), polarimeter, and mass analysis, whereas the structural properties of heterogeneous catalysts C ₂ -BSi@SBA-15, C ₂ -BSi@MCM-41, C ₂ -BSi-MON-(a), and C ₂ -BSi-MON-(b) were determined by FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and N₂ sorption analyses. The catalytic activities of novel heterogenous materials were tested in the reaction of Ti-promoted enantioselective diethylzinc addition to aromatic aldehydes. The effects of the structural arrangements of the prepared heterogeneous catalyst on the catalytic activity were examined and compared with the catalytic activity values of their homogeneous analog. According to the results, all catalysts catalyzed the reactions and afforded the corresponding products with high conversion (82–99%) but low enantioselectivity (rac-7% ee). The conversion values in heterogeneous catalysis were higher than those in homogeneous catalysis. C ₂ -BSi-MON-(a) with the largest pore width stood out as the most effective catalyst (99% conversion, 7% ee). The findings from the catalytic activity experiments confirmed that the structural arrangement of the nanocatalysts has an effect on the performance of the catalysts in the reaction.

Glucose is converted to 5-HMF catalyzed by the mixed-metal metal–organic frameworks.

5-hydroxymethylfurfural (5-HMF) has been considered as an important biomass-based platform chemical for its wide applications. Currently, the production of 5-HMF from the catalytic dehydration of glucose is preferred, in which the Brønsted and Lewis acids in catalysts play an important role. Here, it was found that MIL-53(Al) modified with tin was an active, selective, and reusable catalyst for the transformation of glucose to 5-HMF in dimethyl sulfoxide (DMSO) solvent. Around 42.3% yield of 5-HMF with 93% glucose conversion was achieved, when the prepared metal-organic frameworks (MOFs) was used as the catalyst, showing superior catalytic performance compared with most of other MOFs. Moreover, the catalyst possessed inert catalytic properties in water with almost no any influence on the conversion of glucose, suggesting a compelling opportunity to act as a support material.

This paper reported a new convenient, low energy consumption, rapid, and eco-friendly synthesis of silver nanoparticles (AgNPs) by using ovalbumin (OVA) and visible light irradiation (OVA-AgNPs). In vitro antibacterial experiments showed that OVA-AgNPs have a good antimicrobial effect on both Gram-positive and Gram-negative bacteria, fungi, and some drug-resistant bacteria species.

Silver nanoparticles (AgNPs) are one of the most widely used antimicrobial agents. However, due to the potential problems of environmental pollution and high energy consumption, a green and efficient synthesis strategy of AgNPs is urgently required. Ovalbumin (OVA) is the most abundant protein in egg whites, and its extraction process is simple and productive. This paper reported a new green synthesis method of AgNPs by using OVA as an assistant accompanying with a visible light irradiation. Together with the reduction of silver ions, the uniformly dispersed OVA-AgNPs nanocomposite could be formed within 30 min under xenon light irradiation by simple mixing AgNO₃ and OVA in aqueous solution. The detailed mechanism study showed that tyrosine residue and peptide bonds in OVA played a major role in the reduction and stability of silver ions. In addition, in vitro antibacterial experiments indicated that 10 mg/L of OVA-AgNPs, the minimum inhibitory concentration, has a good antimicrobial effect on both Gram-positive and Gram-negative bacteria, fungi, and some drug-resistant bacteria species within 4 h of treatment, mainly due to the disruption of the structure of bacterial cell and the balance of reactive oxygen species. This work provides a new way for the green and efficient synthesis of AgNPs and shows good prospects for the applications in the field of biomedical materials and functional nanomaterials.

This study synthesized green sol–gel NiFe₂O₄@ZnMn₂O₄ MNCs. X-ray Photoelectron Spectroscopy, X-ray diffraction, transmission electron microscope, field emission scanning electron microscopy, energy dispersive X-ray analysis, vibrating sample magnetometer, Brunauer Emmett Teller, and elemental mapping were employed to characterize the synthesized nanocomposites. NiFe₂O₄@ZnMn₂O₄ MNCs demonstrated outstanding catalytic activity in the microwave-assisted production of tetrahydropyrimidine and polyhydroquinoline derivatives. These magnetic nanocomposites can be easily removed from reactions using an external magnet, and their efficacy remains unchanged even after undergoing four cycles.

In this study, for the first time, NiFe₂O₄@ZnMn₂O₄ magnetic nanocomposites (MNCs) were synthesized using a simple green sol–gel method. The synthesized nanocomposites comprehensive characterized using various analytical techniques including X-ray Photoelectron Spectroscopy, powder X-ray diffraction (XRD), transmission electron microscope, field emission scanning electron microscopy, energy dispersive X-ray analysis, vibrating sample magnetometer, Brunauer Emmett Teller, and elemental mapping. XRD confirmed the spinel crystal structure of NiFe₂O₄@ZnMn₂O₄ MNCs. ZnMn₂O₄ has tetragonal spinel structure while NiFe₂O₄ cubic. In microwave-assisted tetrahydropyrimidine and polyhydroquinoline derivative production, NiFe₂O₄@ZnMn₂O₄ MNCs showed good catalytic activity. An external magnet can remove catalyst from reactions, and their efficacy stays stable after four cycles.

Novel Ru(II) arene complexes were prepared. The cytotoxic activities of these complexes were investigated on MCF-7 cell line. The structure–activity relationships for the complexes containing Namine/Namine, Namine/Namide, Namide/Oamide, and Namide/Sthiolate/Sthiolate-chelating ligands were investigated. The promising results were obtained.

This study focuses on the cytotoxic activity of ruthenium(II) complexes, denoted as Ru1–8, which exhibit coordination with nitrogen (amine and amide), oxygen, and sulfur donor atoms, coupled with aryl and aliphatic wingtips. Specifically, the complexes were evaluated for their impact on the MCF-7 breast cancer cell line. A systematic exploration of various parameters, including solubility, donor atom type, metal number, carbon chain length, aromatic ring presence, and molecular weight, was conducted to discern their influence on cytotoxic activity. The investigation involved assessing the cell viability across five concentrations (100, 50, 25, 10, and 5 μM) for five distinct monometallic and three bimetallic ruthenium complexes. Notably, Ru3, characterized by an extended carbon chain length (dodecyl) and favorable oil solubility facilitating cellular membrane penetration, demonstrated particularly promising results with the IC₅₀ value of 1.03 μM. This research underscores the critical role of ligand design in shaping the cytotoxic potential of ruthenium(II) complexes and emphasizes the suitability of the Ru(II) p-cymene complexes, as demonstrated by their robust activity against breast cancer in this specific investigation.

In this paper, TiO₂-partially reduced graphene oxide (TiO₂-PRGO) nanocomposites were successfully fabricated by a modified one-step solvothermal method and the photocatalytic effect was investigated in experiments. Its photocatalytic efficiency for methylene blue (MB) degradation was maximum seven times than that of pure TiO₂ nanoparticles.

The effect of graphene oxide with different reduction degrees on the photocatalytic efficiency of titanium dioxide-graphene (TiO₂-G) composites has not been systematically studied. In this paper, titanium dioxide-partially reduced graphene oxide (TiO₂-PRGO) nanocomposites were prepared by a modified one-step solvent-thermal method and further reduced with ascorbic acid to obtain TiO₂-PRGO(xh) with a higher degree of reduction (ascorbic acid 80° reduced TiO₂-PRGO x h, x = 1, 2, 3, 4). The composites were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and ultraviolet–visible diffuse reflectance spectroscopy (DRS). The transient photocurrent response and electrochemical impedance results show that TiO₂-PRGO has the most outstanding photoelectrochemical properties. Compared with pure TiO₂ and other samples, the TiO₂-PRGO nanocomposites exhibited excellent photocatalytic properties, and their photocatalytic efficiencies for the degradation of methylene blue (MB) were up to seven times higher than those of the pure TiO₂ nanomaterials, and twice that of TiO₂-PRGO(4h). The photodegradation of methylene blue by the composites decreased as the degree of PRGO reduction increased. The efficient photocatalytic performance of TiO₂-PRGO can be attributed to the high TiO₂ loading and good electrical conductivity. Notably, TiO₂-PRGO photocatalysis for 90 min resulted in 100% degradation of MB. Meanwhile, TiO₂-PRGO has good reusability, and the degradation rate of TiO₂-PRGO remained at 95% after four times of degradation in MB solution.

In this work, surface-modified nickel ferrites were prepared using 4,4′-biphenyldisulfonic acid (BPDSA) as the linker. Thus, obtained material has been characterized using multiple characterization techniques. This well-characterized, stable, robust, recyclable material offers a good conversion in the microalgae lipid extraction oil, various fatty acids for the production of biodiesel through transesterification.

Development of a new and sustainable catalyst is necessary to the society for providing economical technology. Surface modification of nanometal oxides is one of the rapidly growing methods for developing a sustainable catalyst with attractive properties than their parent oxide. In this work, surface-modified nickel ferrites have been carried out using 4,4′-biphenyldisulfonic acid (BPDSA) as the linker. Thus, obtained modified material has been characterized using different techniques such as DLS, FT-IR, TGA, XRD, VSM, and XPS. This well-characterized, stable, robust, recyclable material offers a good conversion in the fatty acid, that is, oleic acid esterification in the presence of methanol in a short period of time (3.0 h). Based on the kinetic study in the oleic acid esterification, it fits in the pseudo first-order kinetics, and activation energy was found to be 60.0 kJ/mol. Further, the potentiality of our catalyst was also tested in the transesterification of various raw materials like mustard oil, olive oil, almond oil, and neem oil. In addition, it provides an excellent conversion with microalgae lipid extraction for the production of biodiesel. The kinematic viscosity of the methyl oleate (biodiesel) has been found to be 5.0426 mm²/s at 25°C whereas the dynamic viscosity is 6.0511 mPa, which is nearly the same as biodiesel obtained from Dunaliella salina, microalgae lipid.

We report the asymmetric epoxidation of R-(+)-limonene using a dimeric racemic Salen Mn (III) complex (5 mol%) in a mixture of KHSO₅ and substrate in the ratio 1:4, respectively, in acetone at ambient temperature to give cis-1,2-(+)-limonene oxide with d.e and d.y.e of 77% and 72%, respectively. Remarkably, the catalyst was easily separated and reused up to four cycles without appreciable loss of catalytic activity in the absence of co-catalysts and nitrogenous bases.

Diastereoselective epoxidation of R-(+)-limonene using achiral and racemic dimeric Salen-Mn (III) complexes as catalysts ((1a) and (1b)) and in situ generated dimethyldioxirane (DMDO) as an oxidizing agent was explored. The best reaction parameters were: (i) KHSO₅/R-(+)-limonene molar ratio = 0.25; (ii) R-(+)-limonene, catalyst molar ratio = 20, (iii) absence of nitrogenous bases (axial ligands), (iv) ambient temperature (20°C), (v) racemic dimeric catalyst, and (vi) low amount of acetone (4 mL). Under these reaction conditions isolated yield to 1,2-(+)-limonene oxide and diastereomeric excess (d.e), and diastereomeric yield excess (d.y.e) to major diastereomer (cis-epoxide) was 96%, 77%, and 72%, respectively. Moreover, the catalyst was segregated into a solid phase, while products remained in the liquid phase, allowing the easy separation of the catalyst and reaction products. Consequently, the catalyst could be recycled up to three times without appreciable loss of its initial catalytic activity.

Two new Schiff base compounds of N-{2-[(E)-сyclohexyliminomethyl]phenyl}-4-methylbenzenesulfonamide, N-{2-[(E)-(4-сyclohexylphenyl)iminomethyl]phenyl}-4-methylbenzenesulfonamide and their Zn(II) complexes have been synthesized and characterized by elemental analysis, FT-IR and UV–Vis spectra, and single crystal X-ray determination. In both complexes, Zn²⁺ ions have a tetrahedral environment with two nitrogen atoms of the tosylamide groups and two nitrogen atoms of the imine fragment. Time-dependent density functional theory calculations have been performed on two zinc(II) complexes in order to assign their experimental UV–visible absorption bands. Zinc(II) complexes showed thermal stability up to 335–340°C under a nitrogen atmosphere by thermogravimetric analysis (TGA). The photoluminescent spectra show that both Zn(II) complexes in the solid state at room temperature emit blue luminescence with high emission quantum yields of 20% and 29%. The doped devices with configurations of indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPD)/4,4′-N,N′ -dicarbazolebiphenyl (CBP):Zinc(II) complex (5%)/1,3,5-tris(N-phenylbenzimidazole-2-yl) benzene (TPBI)/LiF/Al have been fabricated and investigated. The doped device based on the complex with the сyclohexylphenyl substituent of the ligand showed the best electroluminescent characteristics with maximum brightness L_max of 3415 cd/m², maximum current efficiency of 2.8 cd/A, and power efficiency of 1.9 lm/W, while the doped device with emitter on the base of the complex with the сyclohexyl substituent showed slightly worse electroluminescence (EL) performance with L_max of 2105 cd/m², maximum current efficiency of 2.1 cd/A, and power efficiency of 1.6 lm/W.

The importance of MgCl₂·nEtOH adducts in tpolyethylenes is discussed here by chemical dealcoholation. Moreover, due to the industrial and academic importance of this issue, different aluminum-based compounds including triethylaluminum, triisobutylaluminum, and ethylaluminumdichloride were used to provide the target catalysts.

MgCl₂·nEtOH adducts play a major role in the industrial production of polyethylenes. Their chemical dealcoholation, usually accomplished during the catalyst synthesis step, has had a pronounced impact on the microstructure of the final Ziegler–Natta pre-catalysts and the properties of the resulting polymers. Due to the industrial and academic importance of this issue, different aluminum-based compounds including triethylaluminum (TEAL), triisobutylaluminum (TIBA), and ethylaluminumdichloride (EADC) were used in this research in the chemical dealcoholation of a MgCl₂·1.5EtOH adduct, to provide the target catalysts. According to the analytical results, the catalysts synthesized using aluminum compounds (especially TEAL and EADC) generally had a more fractured structure, a smaller particle size and a vast surface area. Aluminum precursors bind to the catalyst structure together with TiCl₄, which is manifested from their higher adsorption energies obtained by DFT calculations, and the presence of Al atom in the elemental analysis. Varying the chemical structure and physical properties of the catalysts, established using Al compounds, caused significant variation in the ethylene polymerization kinetic curves, their related rate constants, and the flow characteristic of the final polymers. The overall results outstandingly affirm that by appropriate choice of the Lewis acid compound, during the chemical dealcoholation of the adduct, various Ziegler–Natta catalysts can be achieved for different polyethylene grades.