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Research on Chemical Intermediates - In this paper, tributyl(carboxymethyl)phosphonium bromotrichloroferrate as a new magnetic ionic liquid bearing acetic acid tags was synthesized and...  相似文献   
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We have developed green, efficient and powerful protocols for the preparation of 2,4,6‐triarylpyridines and 1,8‐dioxodecahydroacridines in the presence of Fe3O4@TiO2@O2PO2(CH2)2NHSO3H as a sulfonic acid‐functionalized titana‐coated magnetic nanoparticle catalyst under mild and solvent‐free reaction conditions. These protocols furnished the desired products in short reaction times with good to high yields (20–40 min and 80–86% in the case of 2,4,6‐triarylpyridines; 15–90 min and 80–93% in the case of 1,8‐dioxodecahydroacridines). The final step of the mechanistic route in the synthesis of 2,4,6‐triarylpyridines proceeds via an anomeric‐based oxidation. Also, the nanomagnetic core–shell catalyst can be recycled and reused in both cases of the scrutinized one‐pot multicomponent reactions with high turnover number and turnover frequency.  相似文献   
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Research on Chemical Intermediates - Since it has been cleared that a fake compound has been sold to us as cyanoform.  相似文献   
4.
In the present investigation, a novel bifunctional oxyammonium-based ionic liquid, namely, 2,2′-(ethane-1,2-diylbis[oxy])bis(ethan-1-aminium)-2,2,2-trifluoroacetate, was designed and synthesized. The structure of the titled ionic liquid was characterized using Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1HNMR), carbon nuclear magnetic resonance (13CNMR), fluorine nuclear magnetic resonance (19FNMR), homonuclear COSY nuclear magnetic resonance (NMR), thermogravimetry (TG), derivative thermogravimetry (DTG) analysis, X-ray diffraction patterns (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The described ionic liquid demonstrated robust catalytic performance in the synthesis of pyrano[4,3-b]pyrans and tetrahydrobenzo[b]pyran derivatives. The ionic liquid presents a high potential of recycling and reusing capability in both types of model reactions.  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 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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Research on Chemical Intermediates - In this investigation, a new application of 1H-imidazol-3-ium tricyanomethanide catalyst was explored. The catalyst presented a robust catalytic applicability...  相似文献   
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A novel nanomagnetic supported thiourea–copper(I) complex and inorganic–organic Takemoto‐like hybrid nanomagnetic catalyst was designed, and synthesized. The prepared naomagnetic catalyst was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, energy‐dispersive X‐ray analysis, transmission and scanning electron microscopies, thermogravimetry, nitrogen adsorption/desorption, zeta potential and vibrating sample magnetometry. Furthermore, the fabricated dual‐role inorganic–organic hybrid catalyst shows a striking and robust catalytic activity for the synthesis of triazoles and benzamides through click and coupling reactions, respectively, under mild and eco‐friendly reaction conditions.  相似文献   
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A novel and task‐specific nano‐magnetic Schiff base ligand with phosphate spacer using 2‐aminoethyl dihydrogen phosphate instead of usual coating agents, i.e. tetraethoxysilane and 3‐aminopropyltriethoxysilane, for coating of nano‐magnetic Fe3O4 is introduced. The nano‐magnetic Schiff base ligand with phosphate spacer as a novel catalyst was synthesized and fully characterized using infrared spectroscopy, X‐ray diffraction, scanning and transmission electron microscopies, thermogravimetry, derivative thermogravimetry, vibrating sample magnetometry, atomic force microscopy, X‐ray photoelectron spectroscopy and energy‐dispersive X‐ray spectroscopy. The resulting task‐specific nano‐magnetic Schiff base ligand with phosphate spacer was successfully employed as a magnetite Pd nanoparticle‐supported catalyst for Sonogashira and Mizoroki–Heck C–C coupling reactions. To the best of our knowledge, this is the first report of the synthesis and applications of magnetic nanoparticles of Fe3O4@O2PO2(CH2)2NH2 as a suitable spacer for the preparation of a designable Schiff base ligand and its corresponding Pd complex. So the present work can open up a new and promising insight in the course of rational design, synthesis and applications of various task‐specific magnetic nanoparticle complexes. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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