ISSN : 2645-7776
Published by: Sami Publishing Company (10.33945)
Total articles ≅ 52
Latest articles in this journal
Chemical Methodologies, Volume 4, pp 532-542; https://doi.org/10.33945/sami/chemm.2020.4.12
In this research study, four iron (II) complexes of tetradentate N2O2 Schiff base ligands with the general formula of Fe((MeO-bph)2 Am) (Am=1,2-ethyelenediamine (1), 1,3-propanediamine (2), 1,4-buanediamine (3) and 2,2-dimethyl-1,3-propanediamine (4) were synthesized and characterized using the elemental analysis (CHN) and FT-IR spectroscopy. Thermal properties and decomposition stages of all the complexes were evaluated. Finally, all complexes were decomposed at 600 °C for 3 h and the dark precipitates were characterized using the FT-IR, XRD and SEM. FT-IR and XRD results revealed that the precipitate were the pure phase of rhombohedral of magnetite (α-Fe2O3) nanoparticles. The SEM images showed that, the morphology of the precipitate was a relatively spherical shape and average diameter of 40-70 nm. The results of the thermogravimetric analysis the iron (II) complexes showed that the complexes 1–4 were stable until 140-200 °C. However, after that, all the complexes 1–4 decomposed in two stages at various temperatures.
Chemical Methodologies, Volume 4, pp 514-531; https://doi.org/10.33945/sami/chemm.2020.4.11
In this work, stepwise reaction mechanism of the [2+3] cycloaddition reaction among alkyl isocyanides (contains tert-butyl isocyanide, cyclo hexyl isocyanide) with dialkyl acetylenedicarboxylate (contains dimethyl acetylenedicarboxylate, diethyl acetylenedicarboxylate and di-tert-butyl acetylenedicarboxylate) at the presence of acetic anhydride was investigated both in the gas phase and in solvent was studied theoretically. The potential energy of all structures participated in the reaction path was evaluated. The geometry of all the structures participated during the reaction path, the rate-determining step, and potential competitive routes during the reaction coordinate were evaluated. Also, dielectric constant effect of the solvent, the effect of substituted alkyl groups on the potential energy surfaces, and the best product configuration were investigated based upon the quantum mechanical calculations. For better understanding of the molecular interaction, the natural bond orbital method (NBO) and AIM analysis were applied. The results indicated that, the first step of the reaction was recognized as rate-determining step and the reaction rate was predicted to be dependent on the concentration of alkyl isocyanides and dialkyl acetylenedicarboxylate. It was also found that, the electron donating of different alkyl groups was not the main factor for the variation in the potential energy surfaces of the reaction; however, the steric factor of the bulky alkyl groups participating in the reaction path was found to be the main factor.
Chemical Methodologies, Volume 4, pp 400-407; https://doi.org/10.33945/sami/chemm.2020.4.3
N,N,N',N'-tetramethyl-N,N'-bis(sulfo)ethane-1,2-diaminium mesylate ([TMBSED][Oms]2) is used as a highly efficient and dual-functional catalyst for the one-pot multi-component condensation of 2-naphthol with arylaldehydes and thioacetamide under green, mild (70 °C), and solvent-free conditions. In this reaction, 1-thioamidoalkyl-2-naphthols are produced in high to excellent yields and in relatively short reaction times. In this reaction, products are identified by analysis of its 1H NMR, 13C NMR, and FT-IR data. Moreover, a plausible mechanism based on dual-functionality of the catalyst was proposed.
Chemical Methodologies, Volume 4, pp 369-377; https://doi.org/10.33945/sami/chemm.2020.4.1
In this work, four fatty acid derivatives including, methyl tritriacont-17-en-1-oate 1, (9Z, 12Z)-ethyl octadeca-9,12-dienoate 2, stearic acid 3, and 21-acetyl tetracosanoic acid 4 were isolated from acetone extract of the stem barks of Albizia amara by chromatographic separation [TLC and CC]. The structures of the isolated compounds were established on the basis of extensive spectroscopic studies including 1D, 2D-NM, and MS analysis, and compared with literature. Compound 1, 2 and 3 were reported first time from the Albizia genus and compound 4 was a new phytoconstituent isolated for the first time from plant sources.
Chemical Methodologies, Volume 4, pp 477-493; https://doi.org/10.33945/sami/chemm.2020.4.9
This study investigates the uptake of the nickel (II) metal ions from aqueous sources using the xanthan magnetic biocompatible nano-composites. The desired nano-sorbent was first synthesized, analysed, and evaluated by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy and (FT-IR), then used as adsorbent for removing the nickel from aqueous solution. Then the effect of different parameters such as contact time, adsorbent amount, pH, initial concentration, and temperature on the adsorption rate was investigated. The equilibrium time for the stirring state was 60 min and the optimum adsorbent value was 0.1 g and the acidity of 4 was the best pH. The highest removal efficiency was obtained at 97.6%. The kinetic studies of nickel removal by the synthesized adsorbent were performed and the results obtained for batch experiments follow the pseudo-quadratic kinetic model with (R2=0.9987). Equilibrium adsorption studies also revealed that, the adsorption process was in better agreement with the Freundlich isotherm (R2=0.9978). The positive Gibbs free energy (15.08 KJ/mole-1) showed that the process was spontaneous. Also the entropy changes was positive (0.03 KJ/mole-1), indicated an increase in entropy during the adsorption process in the system. Therefore, the adsorption process was associated with increasing the disorder.
Chemical Methodologies, Volume 4, pp 408-423; https://doi.org/10.33945/sami/chemm.2020.4.4
This work provides an overview on applicability of 12 principles of green chemistry. Green chemistry is a term that indicates the creation of chemical products and procedures that reduces the use and production of harmful materials. The goals of green chemistry for protecting the environment can be achieved via several main directions. Some of them are bio-catalysis, use of alternative repeatable raw materials (biomass), alternative reaction solution (such as ionic liquids, supercritical fluids, water), alternative reaction circumstances (microwave activation) as well as to new photocatalytic reactions. Moreover, keep natural resources on earth without using harmful materials is the main objective of green chemistry. By changing patterns of consumption and production, steps are being taken to decrease the pollution and harmful waste, which considered being one of the important goals of green chemistry. Also, it was found that, it is so serious to develop alternative technologies that are safer for both human health and the environment to prevent any further damage to human health and the environment such as reducing release of dangerous chemicals to air leading to reduce damage to lungs. In addition, design safer chemical found to be a good opportunity to improve some chemical methods via producing cleaner and cheaper products in industrial processes when harmful chemicals are replacing with biological enzymes. For all the reasons outlined here, in this review, 12 principles of green chemistry are outlined with their applications, where shows how green chemistry reduces the impact of chemical processes on the environment and how their benefit can be achieved. And, also disadvantages of 12 principles are discussed, as well.
Chemical Methodologies, Volume 4, pp 278-399; https://doi.org/10.33945/sami/chemm.2020.4.2
Corrosion has been the greatest problem in oil and gas industry, and many experts have always tried to combat this major problem. This has been given to the corrosion and inspection in oil and gas industry. Corrosion in oil and gas wells is driven by some electrochemical mechanisms, and when the system reaches a temperature below the dew point, the moisture will be converted to liquid and many droplets form on the pipe's wall. The corrosion in pipelines' coatings is one of the main problems in oil and gas industries for which a huge amount of money is spent each year. Coating is the first defense line in front of a corrosive environment in which pipes have been buried. Good function of coating depends on its adhesion to the metal surface. Finally, according to our results in this article, we show that, the chemical compounds inside the coating such as chlorides and sulphides can play an electrolyte role, which accelerates corrosion.
Chemical Methodologies, Volume 4, pp 437-446; https://doi.org/10.33945/sami/chemm.2020.4.6
In this work, multicomponent synthesis of mono and bis spiro-pyrazolopyridines from isatin derivatives, indanedione and 3-methyl-5-aminopyrazole at the presence of 1,4-disulfo-1,4-diazoniabicyclo[2.2.2]octane chloride (DSDABCO) as a novel ionic liquid media is reported. The present methodology offers several advantages such as simple procedure, mild conditions, excellent yields, green media and reduced environmental consequences. The ionic liquid was recovered and reused. The structures of the synthesized spiro-pyrazolopyridine compounds were confirmed by 1H, 13C NMR and FTIR spectral data and elemental analyses.
Chemical Methodologies, Volume 4, pp 494-513; https://doi.org/10.33945/sami/chemm.2020.4.10
In this work, the effect of the functionalized Ni and Pd transition metals on interaction of the mercaptopyridine (MCP) with the boron nitride nanocage (B12N12) was investigated using the density functional theory (DFT) and TD-DFT method. The selected structures were optimized using the cam-B3LYP/Lanl2DZ level of theory. The adsorption energy and enthalpy values of MCP on the surface of pristine, Ni, and Pd functionalized B12N12 nanocage were negative and all adsorption process were exothermic. The results of the recovery time indicated that the pristine B12N12 nanocage with the lowest recovery time was suitable for making sensitive sensor for MCP molecule and the Ni functionalized B12N12 with the most recovery time that was favorable for making the adsorbent of the MCP molecule. The reduced gradient density (RDG) and quantum theory of atom in molecule (QTAIM) outputs revealed that the interaction of MCP with the Ni functionalized B12N12 were stronger than that of the pristine model. The UV-visible results confirmed that the adsorption of MCP on the surface of the Ni functionalized B12N12 with the most value of λmax was suitable as absorbent in UV area.
Chemical Methodologies, Volume 4, pp 447-466; https://doi.org/10.33945/sami/chemm.2020.4.7
First principles calculations were performed to study the neurotransmitters, tricyclic antidepressant drugs and (5,5) carbon nanotube in the gas phase and solution media for comparison purposes. All calculations were performed using DMol3 code in materials studio 5.5. The simulation results revealed that, the nitroxazepine is quite a reactive drug, so that it can act as the electron donating specie in its interacting with carbon nanotube. In addition, the nitroxazepine is the electron acceptor and serotonin and norepinephrine is the electron donor. To explain the interaction of the carbon nanotube, serotonin, and norepinephrine with nitroxazepine, their local reactivity was analyzed through Fukui functions. The results show that the hydrogen bonding between oxygen atoms of the nitroxazepine and OH of the serotonin and norepinephrine has been assigned as the dominant interaction. In order to gain a deeper understanding of the interaction between the nitroxazepine with the carbon nanotube, serotonin and norepinephrine, calculations of binding energies, quantum molecular descriptors, the most important modes of the vibrational frequencies and density of states (DOS) have been carried out.