Journal of the Iranian Chemical Society最新文献

Among the new complexes, metal N-heterocyclic carbene (NHC) complexes have recently gained remarkable attention as they are entirely appropriate prerequisites for effective drug design and quick optimization. Furthermore, N-heterocyclic carbenes (NHCs) like phosphines contain strong σ-donating properties, which can bind to metals and create stable complexes. This article reports a general theoretical discussion on the structures and nature of C_{(carbene/alkenyl)} → M, P → M and C≡C bonds. Also, the influence of changing L and Rʹ groups in some adducts of [RʹC≡C → ML], (M=Cu (I), Ag (I), Au (I); R'=C₁₀H₇, C₉NH₁₂SO₂; L=NHC (R), P (R)₃; and R=F, Cl, Br, H, CH₃, SiH₃, Ph) has been studied. In this context, DFT calculations by PBE-D3/def2-TZVP level of theory have been used. The nature of C_{(carbene/alkenyl)} → M bonds in [RʹC≡C → MNHCR] and also P → M and C_(alkenyl) → M bonds in [RʹC≡C → MPR₃] complexes was surveyed. This was done using natural bond orbital (NBO), atoms in molecules (AIM), energy decomposition analysis (EDA), and energy decomposition analysis natural orbital for chemical valence (EDA-NOCV). The data have shown that σ donation from C_(alkenyl) to M atom in [RʹC≡C → MPR₃] complexes was greater than corresponding [RʹC≡C → MNHCR] complexes. Also, the C_(alkenyl) → M bonds in corresponding complexes were predominantly electrostatic. In addition, the C≡C bond has been also investigated by applying AIM, EDA, and ETS-NOCV analysis. The outcomes indicate that the highest percentage of interaction energy for C≡C bond is related to covalent interaction.

Dihydropyrimidinone skeleton (DHMP) plays a vital part in medicinal and pharmaceutical chemistry as its derivatives exhibit a broad spectrum of anti-microbial, anti-fungal, anti-bacterial, anti-inflammatory and anti-cancer activities. Taking into account the biological significance of DHPMs, organic chemists have developed different methodologies to synthesize these biologically active target molecules. Our review focuses on the one-pot synthesis of dihydropyrimidinones via Biginelli reaction by using the efficient catalysts and reaction conditions, thereby covering the literature published since 2021.

The present work described the one-pot multicomponent green and novel protocol for the synthesis of dihydrothiazolo [3,2-a] purine-2(1H)-one derivatives from novel purines and substituted 2-amino-thiazoles using BEC (pH 12.5, 10% by weight) as a recyclable heterogeneous catalyst in environmentally sustainable reaction medium PEG-400. The antibacterial potency was studied using a disc diffusion assay against two bacterial strains such as Staphylococci aureus (MTCC 1430) and Escherichia coli (MTCC 1573). The results of biological tests of newly synthesized derivatives 4a, 4b, 4d, 4g, and 4h display marked antibacterial potency against tested pathogens. The biological relevance of these synthesized derivatives is due to the presence of thiazole nucleus in combination with a purine ring. Further, structure conformation of synthesized titled compounds was presented with different spectroscopic methods such as ¹H-NMR, ¹³C-NMR, IR, and GCMS. Numerous benefits of the current method include the catalyst's recyclability, clean reaction conditions, a quick reaction rate, increased product yield, and the lack of dangerous reagents.

We study the effect of high Mg impurity in ZnO film grown by spray pyrolisis for photocatalytic applications. The films were grown on the glass substrate for a very short time (10 min). As a result, pure ZnO film has a nanorice structure with a length of ~ 207 nm, as observed by scanning electron microscopy. By inserting the Mg impurity of ~ 32 at.%, the length of the particle decreased to 90 nm. However, this sample with the high Mg content still exhibits a hexagonal wurtzite structure, as shown by the X-ray diffraction pattern. It was also found that the impurity widens the optical band from 3.20 eV to 3.22 eV, possibly due to the alloying effect. Furthermore, the photocatalytic studies reveal that the ZnO exhibits high degradation efficiency under UV light. By adding Mg impurity, the degradation rate decreases by about 2.93% compared to pure ZnO. After 3 days of exposure, the ZnO and ZnO:Mg demonstrated photocatalytic activity, with a degradation efficiency of 95.33% and 94.17%, respectively. So this result is vital in developing low-cost photocatalytic materials by carefully choosing the type and concentration of doping.

In this work, a micro-solid-phase extraction technique employing polylactic acid (PLA)/ZnO-chitosan bio-nanocomposites was developed to isolate selected triazines from aqueous environments. Subsequently, the isolated analytes were injected into gas chromatography–mass spectrometry instrument following solvent desorption. The PLA bio-nanocomposites, incorporating varying concentrations of synthesized ZnO-chitosan, were fabricated utilizing the solvent casting method. The PLA/ZnO-chitosan bio-nanocomposites and ZnO-chitosan hybrid nanoparticles were analytically characterized by the use of field emission scanning electron microscopy, Fourier-transform infrared spectroscopy, tensile testing, and X-ray diffraction. Tensile tests showed that adding ZnO-chitosan hybrid nanoparticles to PLA increased both its tensile strength and elongation at break. Key parameters of the extraction process involving PLA/ZnO-chitosan bio-nanocomposites such as nanoparticle concentration, ionic strength, sample pH, extraction duration, and solvent choice were meticulously examined and optimized. The refined extraction device exhibited high sensitivity and rapidity, achieving analytical parameters with a detection limit ranging from 0.85 to 2.5 ng L⁻¹ and a quantification limit between 5 and 10 ng L⁻¹. Equilibrium was attained within 20 min. Over a concentration range of 10–1000 ng L^–1, the method showed linearity, with a correlation value higher than 0.9997. Having a relative standard deviation between 4 and 8%, repeatability was confirmed at 100 ng L⁻¹. Ultimately, the proposed extraction device’s effectiveness was confirmed by successfully recovering specific analytes from natural water samples, with relative recovery percentages ranging from 98 to 102%, indicative of negligible matrix interference.

Heavy metal contamination especially in aqueous media has become an important risk to human health and environment. Therefore, due to the broad distribution of barium (Ba²⁺) and strontium (Sr²⁺) ions in the environment and wide variety of their harmful health effects for human, development of efficacious systems for their accurate and selective determination is of great importance. Aiming to develop a point-of-care and easy-to-use sensing device, a paper-based colorimetric sensing device was designed for simultaneous measurement of Ba²⁺ and Sr²⁺ ions standing on the basis of the color change of sodium rhodizonate (SR) in the presence of various concentrations of the target analytes. These color changes were photographed using a smartphone, and after analyzing with Photoshop 2022 software, the average variations in the intensities of colors (RGB (red, green, blue) model) were used to draw the calibration curves. The quantitative identification of Ba²⁺ and Sr²⁺ ions in a single solution was carried out by masking one of them at a moment. The average color intensities (G) displayed a linear relationship with the concentration of the analytes in the ranges of 5––300 ppm and 5–350 ppm with the limit of detection (LOD) values of 3.64 and 4.75 ppm for Ba²⁺ and Sr²⁺ ions, respectively. Moreover, the selectivity of the proposed analytical device was assessed; SR was selective for the target analytes versus the other ions causing a considerable color change. Furthermore, the practical application of this colorimetric device was investigated by the excellent performance in real samples indicating its potential for field applications.

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This article proposes a greener and more efficient method for preparing 9-fluorenone from fluorene via ozone oxidation and the use of micro-nanobubble technology. The effectiveness of ozone micro-nanobubble mass transfer in different polar organic solvents was first studied. Equilibrium concentrations of ozone were higher in alcoholic solvents than in solvents such as ethyl acetate, acetone, dichloromethane, chloroform, and 1,2-dichloroethane, which showed similar equilibrium concentrations of ozone. The variation in hydrogen bonding or dipole–dipole interactions between ozone and solvent molecules caused this change in solubility. Using ethyl acetate as the ideal solvent, with an ozone: fluorene molar ratio of 1.6:1 and reaction duration of 90 min, optimal conditions for ozone oxidation resulted in a 66% yield of 9-fluorenone. We also postulated the chemical mechanism involved in fluorine oxidation by ozone. The presence of hydroxyl radicals during the reaction was confirmed via electron paramagnetic resonance spectra. Indirect ozone oxidation predominated in particular reactions. No requirement of a catalyst and ease of this method makes it well suited for the large-scale manufacturing of 9-fluorenone.

The demand of 4-hydroxybenzoic acid (4-HBA) has increased due to their promising properties in the various industries such as pharmaceutical, cosmetic, and plastic sectors. Mostly 0.005 to 0.035 mol/liter of 4-HBA was observed in the waste stream or fermentation broth. Hence, this work presents a schematic study of 4-HBA separation from the aqueous phase by physical extraction method using conventional and natural solvents (CANS). The harmless and eco-friendly green solvents such as alsi (flaxseed) oil, castor oil, and conventional solvents such as diethyl carbonate, diethyl succinate, and xylene are employed in the extraction experiments. Several parameters, such as the K_DHBA, %E_HBA, P_HBA, and the D_HBA, were examined. The parameters were examined to evaluate the equilibrium for this physical extraction experiment. The obtained results showed the following trend of K_DHBA and %E_HBA, respectively, diethyl carbonate (0.951, 48.75%) > alsi oil (0.565, 36.12%) > diethyl succinate (0.504, 33.51%) > castor oil (0.457, 31.35%). > xylene (0.283, 22.06%).

Graphical abstract

The novel heterogeneous catalyst, Bimetallic-organic framework (Fe, Cu)/carbon nanotubes encapsulated Ni nanoparticles, has been introduced for efficient degradation of acid orange 7 (AO7) via Fenton-like process. Optimizing and modeling of the heterogeneous degradation process were performed using response surface methodology (RSM) based on a five-level central composite design (CCD). The study on the individual and interaction effect of four operating parameters including pH, H₂O₂ concentration (mM), catalyst dose (mg L⁻¹) and reaction time (min) revealed that the maximum AO7 degradation efficiency (93.94%) was achieved under optimal conditions of pH = 4.0, H₂O₂ concentration = 25 mM, catalyst dose = 200.0 mg L⁻¹ and reaction time = 27 min (k = 0.1024 (min⁻¹)). Analysis of scavenging revealed that tertiary butyl alcohol (TBA) led to a notable reduction in the degradation of AO7 under optimal conditions. The degradation of AO7 dropped from 93.94% to 14.28% as TBA concentrations varied from 0 to 9 mmol L⁻¹. Consequently, the rate constant of the degradation reaction decreased from 0.1002 to 0.0058 min⁻¹ as the concentration of the quenching agent increased. Interestingly, it was found that besides the role of Fe, Cu and Ni species in the Fe_0.6Cu_0.3Ni_0.1(BDC)@CNT, surface oxygen-functional groups on the CNT provides faster and efficient Fe(III)/Fe(II) cycle over a broader pH range. Furthermore, concerning the importance of economic and environmental issues, the possibility of regenerating the Fe_0.6Cu_0.3Ni_0.1(BDC)@CNT catalyst for four consecutive cycles has been confirmed. The concluding observations of this study provide favorable outcomes in the development and utilizing the advanced MOF-based catalysts with the aim of effective environmental remediation.

Graphical Abstract

In the current work, a novel and simple electrochemical sensing platform was built utilizing a graphene oxide (GO)/metal–organic framework-235 (MOF-235) nanocomposite, which was successfully synthesized and used as an excellent modifier to determine the simultaneous presence of two key anticancer medications, daunorubicin (DNR), and dacarbazine (DTIC). Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, field-emission scanning electron microscopy, and scanning electron microscopy (SEM) are used to characterize the GO/MOF-235 nanocomposite. The electrocatalytic properties of the modified sensor based on MOF and GO in phosphate buffer solution (PBS) (0.1 M—pH 7.0) toward DNR redox reaction were thoroughly investigated using electrochemical methodologies including cyclic voltammetry, differential pulse voltammetry, and chronoamperometry. This GO/MOF-235-modified CPE demonstrated a wide linear response of 0.005–400.0 μM under optimized conditions. It was determined that 0.002 μM was the detection limit. This sensor displayed two distinct oxidation peaks at 390 mV for DNR and at 750 mV for dacarbazine (DTIC) (peak potential separation = 360 mV), allowing for the simultaneous detection of the two anticancer medications. Determination of these anticancer medicines in samples (DNR injection and DTIC injection) was effectively accomplished in the final step using the GO/MOF-235/CPE sensor.