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1.
Solutions of nitronium tetrafluoroborate in acetonitrile prepared by anodic oxidation of nitrogen dioxide, efficiently nitrate aromatics, enolsilyethers, alkenes and conjugated dienes to afford respectively nitroaromatics, α-nitroketones, vicinal nitroamides and mixtures of nitroacetamides by 1,2- and 1,4-addition.  相似文献   
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Pseudo-first order reaction rate constants of 5,10,15-tris(pentafluorophenyl)corrole Mn(V)-oxo (F15CMn(V)-oxo),5,15-bis(pentafluorophenyl)-10-(phenyl)corrole Mn(V)-oxo(F10CMn(V)-oxo),5,15- bis(phenyl)-10-(pentafluorophenyl)corrole Mn(V)-oxo(F5CMn(V)-oxo) and 5,10,15-tris(phenyl)corrole Mn(V)-oxo(F0CMn(V)-oxo) with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn(V)-oxo corrole and alkene is solvent-dependent.  相似文献   
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An FMOC-protected 2'-hydroxyethyl uridine phosphoramidite has been used to synthesise fluorescein-labelled HyBeacon probes and "FAM-ROX" dual-labelled fluorogenic oligonucleotides.  相似文献   
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Summary The application of capillary SFC for SIMDIST investigations of paraffins and waxes is reported. Pressure, density and temperature of the mobile phase are optimized to obtain high chromatographic resolution of complex mixtures of industrial products. Isothermal linear pressure programming and asymptotic pressure and density programming are used in the range from 15 to 35 MPa in the isothermic mode above 100°C. SFC chromatograms of natural and synthetic paraffins, microcrystalline wax and candle wax are compared. The retention behaviour of paraffin mixtures and waxes has been investigated on methyl/phenyl and biphenyl capillary columns. The polarity of the stationary phases influences the absolute retention time more than it influences the chromatographic resolution.  相似文献   
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Green chemistry can strongly attract students to chemistry. We, therefore, developed a green chemistry educational game that motivates students at the undergraduate and advanced high school levels to consider green chemistry and sustainability concerns as they design a hypothetical, chemical product. The game is intended for incorporation into any chemistry course for majors and non-majors that teaches sustainability and/or the Principles of Green Chemistry at the undergraduate level. The game is free of charge and encourages students to think like professional chemical designers and to develop a chemical product with respect to function and improved human and environmental health. This computer simulation has been assessed by educators and can be seamlessly integrated into an existing curriculum.  相似文献   
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4,8-Dimethylbicyclo [3,3,1]nona-3,7-diene-2,6-dione with hydrazine gives a tetracyclic bishydrazone having two double bonds at bridgehead positions; the chemistry of hydrazo-and azo- compounds derived from this bishydrazone is described.  相似文献   
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