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31.
Mahsa Kiani Mojtaba Bagherzadeh Soraia Meghdadi Farzaneh Fadaei-Tirani Maryam Babaie Kurt Schenk-Joß 《应用有机金属化学》2020,34(11):e5911
The new Co(II) - carboxamide complex ( 1 ) and Co3O4 nanoparticles ( 2 ), by way of thermal decomposition of ( 1 ) have been efficiently synthesised in the environment-friendly. X-ray diffraction reveals a slightly distorted octahedral coordination of cobalt (four nitrogens and two oxygens) in ( 1 ) and regular octahedral or tetrahedral ones (oxygens only) in ( 2 ). The investigation of ( 1 ) and ( 2 ) in the Mizoroki-Heck and epoxidation of alkens reactions showed them both to be powerful, green and inexpensive catalysts. 相似文献
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Chromatographia - Drug scheduling has directed the testing approaches for forensic laboratories since the 1970s when Cannabis (marijuana and hemp) and its psychoactive constituent,... 相似文献
34.
Mohammad Javad TAGHIZADEH Maryam Saleh MOHAMMADNIA Masoumeh GHALKHANI Esmail SOHOULI 《高等学校化学研究》2022,38(2):546-551
Azaperone, with anti-anxiety and anti-aggressive activities used in veterinary medicine, is a member of the butyrophenone class. It is ordinarily utilized for a wide range of indications, such as sedation, obstetrics, and anesthesia. In this research, an improved synthetic route is presented for azaperone using a phase-transfer catalyst(PTC). In general, it was synthesized as a dopamine antagonist in four steps. The bis(2-chloroethyl) amine intermediate is easily obtained after the conversion of the alcohol groups into the chloride leaving group using thionyl chloride(95% yields). The alkylation of commercially available 2-amino pyridine in the presence of PTC was then carried out, giving 1-(pyridin-2-yl) piperazine with 75% yield. 1-(Pyridin-2-yl) piperazine was finally alkylated using 4-chloro-1-(4-fluorophenyl) butan-1-one to achieve azaperone with 60% yield. The butyrophenone intermediate was obtained via the Friedel-Crafts reaction of fluorobenzene with 4-chlorobutyryl chloride in the presence of AlCl3. High efficiency, gentle reaction conditions, and fast and simple procedure are the advantages of this method. Also, the electrochemical oxidation behaviour of azaperone was investigated using cyclic and differential pulse voltammetry techniques. Cyclic voltammetric studies indicated an irreversible process for azaperone electro-oxidation with a peak potential of 0.78 V in a phosphate buffer solution(pH=7.0) vs. Ag/AgCl(saturated KCl) electrode. The value of the peak current vs. the azaperone concentration was enhanced linearly in the range of 10―70 μmol/L, and the detection limit was found to be 3.33 μmol/L. 相似文献
35.
Maryam S. Sadeghi Mohammad Reza Moghbeli William A. Goddard III 《Journal of polymer science. Part A, Polymer chemistry》2021,59(7):614-626
We followed the self-assembly of high-molecular weight MePEG- b -PCL (poly(methyl ethylene glycol)-block-poly(ε-caprolactone)) diblock and MePEG- b -PBO- b -PCL (poly(methyl ethylene glycol)-block-poly(1,2-butylene oxide)-block-poly(ε-caprolactone)) into micelles using molecular dynamics simulation with a coarse grain (CG) force field based on quantum mechanics (CGq FF). The triblock polymer included a short poly(1,2-butylene oxide) (PBO) at the hydrophilic-hydrophobic interface of these systems. Keeping the hydrophilic length fixed (MePEG45), we considered 250 chains in which the hydrophobic length changed from PCL44 or PBO6- b -PCL43 to PCL62 or PBO9- b -PCL61. The polymers were solvated in explicit water for 2 μs of simulations at 310.15 K. We found that the longer diblock system undergoes a morphological transition from an intermediate rod-like micelle to a prolate-sphere, while the micelle formed from the longer triblock system is a stable rod-like micelle. The two shorter diblock and triblock systems show similar self-assembly processes, both resulting in slightly prolate-spheres. The dynamics of the self-assembly is quantified in terms of chain radius of gyration, shape anisotropy, and hydration of the micelle cores. The final micelle structures are analyzed in terms of the local density components. We conclude that the CG model accurately describes the molecular mechanisms of self-assembly and the equilibrium micellar structures of hydrophilic and hydrophobic chains, including the quantity of solvent trapped inside the micellar core. 相似文献
36.
Nanomagnetically modified vitamin B3 (Fe3O4@Niacin): An efficient and reusable green biocatalyst for microwave‐assisted rapid synthesis of 2‐amino‐3‐cyanopyridines in aqueous medium 下载免费PDF全文
Superparamagnetic nanoparticles of modified vitamin B3 (Fe3O4@Niacin) represent a new, efficient and green biocatalyst for the one‐pot synthesis of 2‐amino‐3‐cyanopyridine derivatives via four‐component condensation reaction between aldehydes, ketones, malononitrile, and ammonium acetate under microwave irradiation in water. This new magnetic organocatalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least six times without significant degradation in the activity. The catalyst was fully characterized by FT‐IR, XRD, SEM, VSM, UV–Vis, DLS and EDS. Excellent yield, very short reaction time (7–10 min), operational simplicity, easy work‐up procedure, avoidance of hazardous or toxic catalysts and organic solvents are the main advantages of this green methodology which makes it more economic than the other conventional methods. 相似文献
37.
Tungstate ions were successfully loaded onto triazine‐based ionic liquid‐functionalized magnetic nanoparticles through an anion exchange process. The use of triazine core for creating ionic liquid led to the immobilization of high amounts of WO42?. The resulting catalyst showed high activity and selectivity in the oxidation of sulfides to sulfoxides with H2O2 as a green oxidant at room temperature. In addition, due to the presence of ammonium groups in the catalyst structure, water dispersibility of the catalyst was increased. More important, the catalyst was magnetically recovered and reused for up to six runs without any marked decrease of activity and selectivity. Finally, easy gram‐scale oxidation of methylphenyl sulfide as well as fast separation of catalyst and product makes the protocol economical and industrially applicable. 相似文献
38.
Haleh Kangarlou Arash Abdollahi Maryam Motallebi Aghgonbad 《Optics and Spectroscopy》2012,113(3):321-326
Zinc sulfide nano layers were deposited on glass substrates at 300 K by physical vapor deposition method, under high vacuum conditions and different deposition angles. Thickness of the layers were measured 73 nm, by quartz crystal method. Optical reflectance and transmittance of the layers were measured in the wave length of 300?C1100 nm. Optical constants were calculated by Kramers-Kronig relations. The influence of deposition angle in optical properties of ZnS nano layers are investigated. By using Generalized Gradient Approximations in context of plane wave pseudo-potentials (norm conserving and Ultrasoft) and full-potential linearized augmented plane wave methods, Band structure calculated and compared with experimental results. Possible energy transitions are also reported. 相似文献
39.
Shirini Farhad Goli-Jolodar Omid Akbari Maryam Seddighi Mohadeseh 《Research on Chemical Intermediates》2016,42(5):4733-4749
Research on Chemical Intermediates - A novel Brønsted solid acid named poly(vinylpyrrolidonium) hydrogen phosphate ([PVP-H]H2PO4) has been prepared by using H3PO4 and poly(vinylpyrrolidone) as... 相似文献
40.
Davood Nori-Shargh Maryam Malek Hosseini Tina Ohaninan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2410-2420
An investigation employing the ab initio molecular orbital (MO) and density functional theory (DFT) methods to calculate structural optimization and conformational interconversion pathways for the two diastereoisomeric forms, (±) and meso configurations of 1,3,7,9-tetraphospha-cyclododeca-1,2,7,8-tetraene (1) was undertaken. Two axial symmetrical conformations are found for (±)-1 configuration. (±)-1-TB axial symmetrical form is found to be about 0.35 and 0.99 kcal mol?1 more stable than (±)-1-Crown axial symmetrical conformation, as calculated by HF/6-31G*//HF/6-31G* and B3LYP/6-31G*//HF/6-31G* levels of theory, respectively. The unsymmetrical meso-1-TBCC form is found to be the most stable geometry, among the various conformations of meso-1 configuration. HF/6-31G*//HF/6-31G* and B3LYP/6-31G*//HF/6-31G* results showed that between the two most stable conformations of (±) and meso configurations, (±)-1-TB is more stable than meso-1-TBCC by about 3.35 and 2.43 kcal mol?1, respectively. In addition, MP2/6-31G* and B3LYP/6-311+G** results showed that the (±)-1-TB form is about 1.10 and 2.36 kcal mol?1 more stable than the meso-1-TBCC form. Further, NBO results revealed that in the most stable form of meso configuration (meso-1-TBCC), the sum of the π* allenic antibonding orbital occupancies (Σ π *occupancy) is greater than dl configuration ((±)-1-TB). Also, NBO results indicated that in the (±)-1-TB conformer, the sum of σ and π allenic moieties bonding orbital deviations (Σ σ dev+Σ π dev) from their normal values, is lower than in the meso-1-TBCC form. 相似文献