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71.
72.
《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2343-2348
A simple method for the preparation of industrially important alkyl aryl ethers is reported. Several phenolic compounds such as phenols, naphthols, and hydroxy coumarins were O-methylated with trimethyl phosphite or trimethyl phosphate under microwave irradiation and solvent-free condition in almost quantitative yields. Reaction of 2-naphthol with trimethyl phosphate gave mixture of 2-methoxynaphthalene and 1-methyl-2-methoxynaphthalene while the reaction with trimethyl phosphite gave mostly 2-methoxynaphthalene. This method is highly efficient for the methylating of phenolic compounds with very easy experimental procedure and environmental friendly conditions. 相似文献
73.
74.
Hossein A. Oskooie Azam Ranjbaran Majid M. Heravi Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1711-1714
Reduction of aromatic nitro compounds to amine with hydroiodic acid was revisited. Under microwave irradiation on solid support the reduction proceeded efficiently and rapidly. 相似文献
75.
Jelem Restrepo José Salazar Simón E. López 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2311-2320
Abstract We describe a rapid and convenient methodology for the preparation of diverse 3-aryl and 3-trifluoromethyl 4H-1,2,4-benzothiadiazine-1,1-dioxides in a one-pot microwave-promoted reaction between 2-aminobenzenesulfonamides and benzaldehydes, trifluoroacetic acid or benzoic acids. GRAPHICAL ABSTRACT 相似文献
76.
Majid M. Heravi Hossein A. Oskooie Pegah Kazemian Fatemeh Drikvand Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2341-2344
Cerium ammonium nitrate (CAN) adsorbed on HNO 3 /silica gel is a mild reagent for selective oxidation of benzylic alcohols to the corresponding aldehydes under microwave irradiation in solventless system. 相似文献
77.
Yunzhi Ling Yuqiong Luo Jiwen Luo Xiaoying Wang Runcang Sun 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1194-1200
The optimal conditions for synthesizing quaternized chitosan (QCS) via microwave irradiation were explored. The microwave temperature, time, power, mole ratio between chitosan and 2,3-epoxypropyltrimethyl ammonium chloride (ETA), volume ratio between isopropanol and water, and pH value of the reaction system were studied to evaluate the effect on the degree of substitution (DS). The structure of QCS was characterized by means of FT-IR, NMR, XPS and XRD. TGA and DTG were used to measure its thermal stability. At last, QCS acted as a reducing and stabilizing agent to greenly synthesize gold nanoparticles without adding any other chemical reagent. 相似文献
78.
《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):351-363
ABSTRACT The influence of the presence of an inorganic carrier in the polymerization systems was investigated in this paper. Ten polymerization systems that contained different inorganic carriers such as Al2O3, SiO2 were studied. The ten polymerization systems are dibutyltin Maleate (DBTM) and allyl thiourea (AT), DBTM and stearic acid vinyl ester (SAVE), SAVE and maleic anhydride (MH), SAVE and acrylamide (AM), itaconic acid (IA) and AM, SAVE and IA, AM and MH, IA, sodium acrylate (AANa), AM. It was found that the activity of monomer can be changed in the presence of a carrier and furthermore, the different species of carrier influence the activity of same monomer differently in the polymerization. 相似文献
79.
Microwave (MW) radiation has been used in chemical analysis and chemical synthesis. MW heating under controlled conditions offers distinct advantages over conventional heating. The reactions are carried out in environmentally clean and safe solvents and in many cases, reactions can be carried out under solvent‐free conditions. This method of synthesis has grown rapidly and found its use in various sectors. This paper reviews some of the reactions that have been accelerated with higher yields under MW irradiation. The application of MW‐assisted synthesis in the medicinal and pharmaceutical industries will be emphasized. 相似文献
80.
Shadpour Mallakpour Amin Zadehnazari 《International Journal of Polymer Analysis and Characterization》2013,18(6):469-477
Microwave irradiation was used to accelerate the polycondensation of a new thiazole-containing diamine with several chiral diacids. Polymerization reactions were carried out in molten tetrabutylammonium bromide as a green molten salt medium and triphenyl phosphite as the homogenizer. A series of new compounds were characterized by Fourier transform-infrared spectroscopy, nuclear magnetic resonance spectroscopy, and elemental analysis techniques. The polymeric samples showed high thermal stability with decomposition temperature being above 360°C; they were in a nanoscale size and were assembled uniformly and randomly in a sponge-like morphology. 相似文献