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61.
A facile synthesis of trans isomers of 4‐aryl‐3‐methyl‐6‐oxo‐4,5,6,7‐tetrahydro ‐ 2H ‐ pyrazolo[3,4‐b]pyridine‐5‐carbonitriles via three‐component condensation reaction of an aldehyde, 3‐amino‐5‐methylpyrazole and ethyl cyanoacetate in acetonitrile has been developed under microwave irradiation. This one‐pot reaction proceeds without any catalyst in short times and gives the product in high selectivities and high yields.  相似文献   
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Research on Chemical Intermediates - In the presented study, we developed a new and efficient strategy for the synthesis of coumarin-linked nicotinonitrile derivatives via a cooperative vinylogous...  相似文献   
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In this study, a novel magnetic mesoporous MCM‐41 silica supported ionic liquid/palladium complex (Fe3O4@MCM@IL/Pd) with core‐structure was prepared and characterized and its catalytic performance was developed under green conditions. The Fe3O4@MCM@IL/Pd was prepared via a post grafting method and was characterized using Fourier transform infrared spectroscopy, thermal gravimetric analysis, wide‐ and low‐angle powder X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, vibration sample magnetometer and energy‐dispersive X‐ray analyses. This was applied as an efficient and recoverable nanocatalyst for the one‐pot synthesis of pyrano[2,3‐d]pyrimidine derivatives under ultrasonic conditions. The catalyst was magnetically recovered and reused for 12 consecutive cycles without significant loss of its activity and selectivity.  相似文献   
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International Journal of Theoretical Physics - Reversible logic is used in designing low-power CMOS circuits, optical information processing, and quantum computing. Moreover, using parity...  相似文献   
67.
Some new bis-benzylidene-hydrazides were synthesized via a condensation reaction of the corresponding azo dyes with adipic acid dihydrazide. All compounds because of the three possible stereoisomers showed four sets of signals in NMR. The anion recognition studies exhibited that the nitro bis-benzylidene-hydrazide derivative acts as a highly sensitive and selective chromogenic sensor for naked-eye detection of CN¯ and AcO¯ ions, with a distinct color change from yellow to blue and yellow to purple, respectively. The limit of detection (LOD) was found for 1d toward CN¯ to be 1.1?μM. The result of the Job's plot indicated stoichiometry of binding between chemosensor and anions is found to be 1:2.  相似文献   
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Journal of Solid State Electrochemistry - In this study, the potential of Si14Ge14 and B14P14 as anode electrodes in metal-ion batteries by using of the density functional theory was investigated....  相似文献   
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In the current study, a novel and reusable biological urea based nano magnetic catalyst namely Fe3O4@SiO2@(CH2)3‐urea‐benzimidazole sulfonic acid was designed and synthesized. The structure of the titled catalyst was fully characterized using several skills including Fourier transform infrared (FT‐IR) spectroscopy, energy dispersive X‐ray (EDX) analysis, X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermo gravimetric analysis/differential thermal analysis (TG/DTG) and vibrating sample magnetometer (VSM). Then, the catalytic performance of Fe3O4@SiO2@(CH2)3‐urea‐benzimidazole sulfonic acid was successfully inspected towards the multicomponent synthesis of 2‐amino‐3‐cyano pyridine derivatives through a vinylogous anomeric based oxidation pathway.  相似文献   
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Research on Chemical Intermediates - A new heterogeneous nanomagnetic catalyst bearing morpholine tags was synthesized and characterized. The formation of the nanomagnetic catalyst was fully...  相似文献   
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