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301.
Nanomagnetic‐supported Sulfonic Acid: Simple and Rapid Method for the Synthesis of α,α′‐Bis‐(substituted‐benzylidene) Cycloalkanones 下载免费PDF全文
Nanomagnetic‐supported sulfonic acid is found to be a powerful and reusable heterogeneous catalyst for the rapid synthesis of α,α′‐bis‐(substituted‐benzylidene)cycloalkanones under conventional heating and solvent free conditions. High yield, simple work up and easy recovery of the catalyst are the most obvious advantages of this procedure. 相似文献
302.
Mohammad Navid SoltaniRad Ali Khalafi‐Nezhad Somayeh Babamohammadi Somayeh Behrouz 《Helvetica chimica acta》2010,93(12):2454-2466
A convenient and efficient method for a one‐pot conversion of N‐alkylisatins to N‐alkylisatin O‐alkyloximes 7a – 7n as potential chemotherapeutic agents is described (Scheme) (isatin=1H‐indole‐2,3‐dione). In this method, the microwave‐assisted three‐component reaction of N‐alkylisatins 8 , hydroxylamine hydrochloride, and diverse alkyl halides in the presence of K2CO3 and Bu4NBr furnishes the corresponding N‐alkylisatin O‐alkyloximes under solvent‐free condition in short times (2–10 min) and good to excellent yields (62–83%). The O‐alkylation of in situ generated isatin oximes with alkyl halides was achieved regioselectively, and (Z)‐O‐alkyloximes were produced dominantly. PM3 Semi‐empirical quantum‐mechanic calculations were performed to rationalize the evidences, and the calculations indicated a lower heat of formation for the (Z)‐O‐alkyloximes. 相似文献
303.
Mohammad Navid Soltani Rad Somayeh Behrouz Javad Mohammadtaghi‐Nezhad Elham Zarenezhad Mahmoud Agholi 《应用有机金属化学》2019,33(4)
The preparation, characterization and application of silica‐tethered cuprous acetophenone thiosemicarbazone (STCATSC) as a novel hybrid nano catalyst for synthesis of new 1,2,3‐triazolyl‐based metronidazole hybrid analogues is described. STCATSC is fully characterized by different microscopic, spectroscopic and physical techniques, including scanning electron microscopy (SEM), transmission, X‐ray diffraction (XRD), Energy‐dispersive X‐ray spectroscopy (EDS), thermogravimetric analysis (TGA), FT‐IR and inductively coupled plasma (ICP) analysis. This catalyst is used to prepare the new 1,2,3‐triazolyl‐based metronidazole hybrid analogues. The ‘Click’ Huisgen cycloaddition reaction of 2‐methyl‐5‐nitro‐1‐prop‐2‐ynyl‐1H‐imidazole with diverse β‐azidoalcohols in a THF‐water media at R.T. provides the products in good to excellent yields using STCATSC. STCATSC is proved to be a stable, low cost, reusable and environmentally benign hybrid catalyst. Products are in vitro tested against Giardia lamblia (G. lamblia) in which determined that all compounds exhibit varied promising antigiardial activity compare to metronidazole as a reference drug. Among the products, 1‐(4‐((2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)methyl)‐1H‐1,2,3‐triazol‐1‐yl)‐3‐phenethoxypropan‐2‐ol and 1‐(4‐((2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)methyl)‐1H‐1,2,3‐triazol‐1‐yl)‐3‐(3‐phenylpropoxy)propan‐2‐ol are demonstrated to exhibit the potent antigiardial activity even stronger than metronidazole. 相似文献
304.
An extensive study of Fischer-Tropsch synthesis on nanostructure supports with high surface area such as nanostructure γ-alumina, single wall carbon nanotubes (SWNTs), and the hybrid of SWNTs/nanostructure γ-alumina has been investigated. The nanostructure γ-alumina was promoted with lanthanum to obtain better performance of catalyst and 15 wt% cobalt loading was the basis of our investigation. Fischer-Tropsch synthesis was performed in a fixed bed reactor under different reaction conditions (220–240 °C, 15–25 bar, H2/CO ratio of 2, GHSV of 900–1400) in order to study the effects of temperature, pressure and gas hourly space velocity (GHSV) changes on hydrocarbon selectivity and catalyst activity. The catalysts were extensively characterized by different methods including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), inductively coupled plasma (ICP), hydrogen (H2) chemisorption and temperature-programmed reduction (TPR). The results showed that the yield of hybrid supported catalyst (55.4%) is higher than that of nanostructure γ-alumina supported catalyst (55.0%) and lower than that of SWNTs supported cobalt catalyst (71.0%). The hybrid supported catalyst showed higher reduction degree and dispersion of cobalt particles. The temperature, pressure and GHSV effects on hybrid supported catalyst were studied and results showed that higher pressure favors the chain growth and temperature increase leads to the increases in methane selectivity and CO conversion. Higher hydrocarbon selectivity and CO conversion showed positive relationship with increasing GHSV while lower hydrocarbon selectivity diminishes. 相似文献
305.
Somayeh Tajik Hadi Beitollahi Zahra Dourandish Peyman Mohammadzadeh Jahani Iran Sheikhshoaie Mohammad Bagher Askari Parisa Salarizadeh Fariba Garkani Nejad Dokyoon Kim Soo Young Kim Rajender S. Varma Mohammadreza Shokouhimehr 《Electroanalysis》2022,34(7):1065-1091
Non-precious transition metal oxide nanomaterials offer numerous opportunities for various cost-effective electrochemical applications. This review article features the design and advancement of such nanomaterials with unique features applied for the fabrication of electrochemical devices. Also, it discusses various new syntheses of transition metal oxide nanoparticles (TMO NPs) via multiple chemicophysical and biological procedures. Further, the novel appliances of the TMO NPs with varying sizes and morphologies are appraised. The advantages and challenges of a number of investigations on the TMO NPs towards electrochemical applications are addressed with their standpoint of cost-effectiveness, applicability, and the efficiency of the introduced nanostructures for the industrial applications. 相似文献
306.
Nemat Tahmasbi Somayeh Madmoli Parisa Farahnak Shahram Barzegar Hamze Moayeri 《Russian Journal of Applied Chemistry》2017,90(9):1488-1493
In the paper cesium tungstate nanofibers for the first time have been fabricated successfully by a simple electrospinning technique followed by heat treatment. The cesium tungstate nanofibers have been characterized by XRD, SEM, and FTIR techniques. The results indicated the morphology and quality of the annealed electrospun samples are strongly dependent on the citric acid content within electrospinning solution. It is found with increasing the citric acid content from 7 to 22% the samples morphology changed from a particle structure to a fibrous structure. The average diameter of nanofibers was ~350 nm. XRD analysis reveals that all of the samples have good crystallinity with the same diffraction peaks that can be indexed to the tetragonal phase of Cs2W3O10. Furthermore, the photocatalyst properties of cesium tungstate has not been reported to date. In the work the synthesized Cs2W3O10 nanofibers were found to exhibit photocatalytic performance in the photodegradation of RhB aqueous solution used as a pollutant model. 相似文献
307.
Somayeh Sharifi Zarei Ebrahim Asghari Alireza 《Russian Journal of Electrochemistry》2021,57(2):183-196
Russian Journal of Electrochemistry - In the present study, simultaneous voltammetric determination of noscapine and papaverine as two important alkaloids in opium was studied for the first time. A... 相似文献