https://icc.journals.pnu.ac.ir/ Iranian chemical communication en daily 1 Wed, 01 Jan 2020 00:00:00 +0330 Wed, 01 Jan 2020 00:00:00 +0330 https://icc.journals.pnu.ac.ir/article_6130.html Two polypyridyl copper(II) complexes, [Cu(phen)(phen-dione)Cl]Cl (1) and [Cu(bpy) (phen-dione)Cl]Cl (2), (where Phen =1,10-phenanthroline, bpy =2,2'-bipyridine and Phen-dione = 1,10-phenanthroline-5,6-dione), were used as efficient catalysts for the oxidation of benzyl alcohol to benzaldehyde. The effects of various parameters such as reaction temperature, reaction time, etc. were studied. The catalysts were stable at the operation conditions and recyclable. The conversion percentage for complex 1 was higher than the complex 2. https://icc.journals.pnu.ac.ir/article_6270.html In the present research, salting out and vortex assisted dispersive liquid–liquid microextraction based on solidification of floating organic drop microextraction (SO-VADLLME-SFODME)  for the extraction and determination of phenol and chlorophenols in water samples followed by HPLC have been studied through a novel, simple, low-cost, selectable and environment friendly (so called green) method. Three approaches have been combined in a way that their advantages have been used while reducing their deficiencies. The effects of various empirical parameters such as pH, type and volume of dispersive solvent, the volume of extracted organic solvent, salt concentration, the condition of centrifuge, and mixing time were studied and optimal conditions were achieved by using Mini-Tab software and Respond Surface Methodology (RSM) based upon Box-Behnken Design (BBD) and Desirability Function (DF). Under the optimum conditions, calibration curves were linear in the range of 0.1 to 1000 μgL-1, limit of detections (LODs) were in the range of  0.06 to 0.34μgL-1 and r2>0.9916, respectively. The method was also utilized to measure phenol and chlorophenols in various water samples successfully resulted in extraction recoveries ranged from 92.8 to 103.9%. https://icc.journals.pnu.ac.ir/article_6281.html A single-use electrochemical sensor using ionic liquid mediated hollow fiber-graphite working electrode was fabricated for the first time. The screening tool was developed by coupling this electrode with differential pulse voltammetry (DPV) for in-situ pre-concentration and determination of Zn(II) and Cu(II). In our plot, porous polypropylene hollow fiber membrane was divided into pieces of 2 cm, then fiber's lumen and pores were satiated with homogeneous mixture of reduced graphene oxide (rGO) and three types used ionic liquids:(1-ethyl-3-methylimidazolium tetrafuoroborate), (1-butyl-3-methylimidazoliumhexafluorophosphate) and (1-butyl-2,3-dimethylimidazolium hexafluorophosphate) individually. Thereafter, a pencil graphite rod was placed inside the fiber. Fabricated sensors were used for single-step simultaneous purification and determination of Zn(II) and Cu(II) ions from water samples. The response surface method (RSM) was used as the basis of the design and analysis of the experiments. Parameters that were mostly important in the separation part of the study, such as: molar mass of ionic liquids, amount of nanoparticle and sonication time have been investigated. Analysis of variance (ANOVA) and RSM contour plots were presented for effect of all factors (input parameters) on the maximum current of differential pulse voltammetry (DPV) peaks (output responses). The results disclosed that the metal removal was impressed by the molar mass of ionic liquids, amount of nanoparticle and sonication time respectively. The efficiency specifications of this procedure were evaluated by calculating precision and response linearity. Under the optimal experimental conditions linear concentration ranges of 0.9–550µgL-1 and 0.7–500 µgL-1 were obtained for Zn(II) and Cu(II) ions respectively. The reported limit of detection for Zn(II) and Cu(II) were 0.27 and 0.21µgL-1 with relative standard deviations (RSD) 3.2%, and 4.4%, respectively. In addition, this sensor was successfully applied to real water samples. https://icc.journals.pnu.ac.ir/article_6282.html Benzimidazoles are among the most important nitrogen-containing heterocyclic compounds that have many pharmaceutical applications; including, antitumor, anticancer, anticorrosive, antibacterial, irritant and enzymatic interceptors. In this research, the synthesis of benzimidazoles using o-phenylenediamine and aldehyde derivatives in the presence of the nano montemurillonite in solvent-free and room temperature conditions has been investigated. All products with relatively good yields were identified by spectral and physical methods. https://icc.journals.pnu.ac.ir/article_6283.html Nano-silica-bonded 3-n-propyl-1-sulfonic acid imidazolium chloride (nano-SB-[PSIM]Cl) was applied as a highly efficient, general and heterogeneous catalyst for one pot multi-component reaction of 2-naphthol, arylaldehydes, and thioacetamide leading to 1-thioamidolakyl-2-naphthols. All reactions proceeded with excellent yields in short times under solvent-free conditions. Our protocol was superior than most of the reported methods for the preparation of 1-thioamidolakyl-2-naphthols in terms of some factors included relatively short reaction times, moderate to high yields, and absence of organic solvents.     https://icc.journals.pnu.ac.ir/article_6284.html A green and highly effective solvent-free protocol has been reported for the synthesis of N,N′-alkylidene bisamides via the reaction of arylaldehydes (1 eq.) with primary amides (2 eq.) in the presence of saccharin-N-sulfonic acid (SaSA) as a solid-acid catalyst. The mentioned compounds have been obtained in high yields and short reaction times. https://icc.journals.pnu.ac.ir/article_6297.html The ZnCrFeO4 nanoparticles were synthesized as antiferromagnetic material using sol-gel method. The X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM) certified that ZnCrFeO4 nanoparticles have single-phase cubic structure with a range of 50–100 nm in size. A facile and sensitive analytical method was developed for simultaneous determination of sunset yellow and tartrazine based on ZnCrFeO4 modified paste electrode.  The oxidation responses of sunset yellow and tartrazine are improved extremely at the modified carbon paste electrode (ZnCrFeO4/CPE), exhibiting two well-defined anodic peaks at + 0.70V and +0.99 V vs Ag/AgCl, respectively.  The oxidation reactions were controlled by diffusion step for tartrazine and adsorption step for sunset yellow. Simultaneous determination of these dyes indicated wide linear ranges from 0.07 to 47.5, and 0.05 to 19.0 μmol L−1 with detection limits of 2.0 and  10.0 nmol L−1  for sunset yellow and tartrazine, respectively. The results of real samples analyses  affirmed that ZnCrFeO4/CPE possess remarkable potential to determine simultaneously sunset yellow and tartrazine in soft drinks samples. https://icc.journals.pnu.ac.ir/article_6303.html An efficient and green protocol for the synthesis of 2-arylsubstituted benzimidazoles via a condensation reaction of aromatic aldehydes and 1,2-phenylenediamine using nano-Fe3O4@SiO2-SO3H as a solid acid catalyst in ethanol under reflux conditions has been described. The reactions are completed in short times, and the corresponding benzimidazoles are produced with high yields. The present procedure has several advantages, including short reaction times, high yields of products, facile experiment, simple work-up, eco-friendly reaction conditions, and reusability of the catalyst. The catalyst could simply be separated and recovered by an external magnet and reused several times without appreciable loss of catalytic activity. https://icc.journals.pnu.ac.ir/article_6415.html The current study aimed at in vitro investigating the kinetic study and thermodynamic analysis of mebendazole drug released from electrospun cellulose nanofiber in which guar gum is used as a release controller. The nanofibers were fabricated by electrospinning technique. The fibers were boosted by different controller guar gum 10 at 50, 250, and 500 ppm concentrations. The drug release was investigated on each fiber at 25 °C, 31 °C, 37 °C, and 43 °C for 72 h. The results showed that guar gum can be used as a drug controlling agent in nanofiber. The drug release becomes more difficult where the concentration of guar gum in the nanofiber is higher. Various models for kinetic modeling were investigated, among which the Sahlin-Peppas model fitted the experimental data efficiently. Kinetic studies have shown that both diffusion and swelling mechanisms contribute to the drug release process. This is due to the hydrophilic nature of guar gum. If the value of the controller is greater, the diffusion mechanism dominates the process. Thermodynamic analysis showed that drug release at all controlling concentrations is not spontaneous (ΔG>0) and is an endothermic process (ΔH>0), leading to increased disorder (ΔS<0). Activation energy increases with the increase in the amount of guar gum controller, which means that more energy is needed to release the drug. https://icc.journals.pnu.ac.ir/article_9788.html In this study, Nd-doped cobalt oxide (Nd-Co3O4) nanoparticles were prepared by a combustion synthesis procedure using Co(acac)3 complex. The nanoparticles were characterized by infrared spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Then, the effect of Nd-Co3O4 on the electrocatalytic activity of gold nanodendrites (AuNDs) electrodeposited on a glassy carbon electrode (GCE) for ethanol oxidation was studied. The results showed that the Nd-Co3O4/AuNDs/GCE presents higher active surface area and current density (about 2 times) for the ethanol oxidation compared with the AuNDs/GCE.  Cyclic voltammetry and chrono-potentiometry methods proved that the Nd-Co3O4/AuNDs/GCE is able to increase a long-term stability of electrode in alkaline ethanol fuel cell by providing OHads species at the surface of the catalysts. Consequently, the Nd-Co3O4/AuNDs/GCE, as an anodic electrode, reveals potent catalytic activity for ethanol oxidation in alkaline media.