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971.
N Thorne M Shen WA Lea A Simeonov S Lovell DS Auld J Inglese 《Chemistry & biology》2012,19(8):1060-1072
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972.
Alexey Borisovich Umanskii Anton Mihaylovich Klyushnikov 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(1):193-198
A process of ferrous ion oxidation by sodium nitrite in sulfate uranium in situ leaching solutions was investigated. Kinetic, spectrophotometric, and heat effect studies have been made in order to investigate the chemistry of the oxidation process. As a result the method of ferrous ion oxidation in uranium in situ leaching solution was developed that makes possible to decrease sodium nitrite consumption by 20?C30 times comparing with traditional oxidation technique. It was founded also that process of ferrous ion oxidation can be conducted with partial sodium nitrite recirculation. 相似文献
973.
Building on results for the adsorption of benzene on Pt(111), the adsorption of benzaldehyde is investigated using density functional theory. Benzaldehyde is found to chemisorb preferentially with its aromatic ring in the flat-lying bridge geometry that is also preferred for benzene. Across the investigated geometries, adsorption is homogeneously weakened compared to corresponding benzene geometries. This is found to be true for very different adsorption modes, namely, η(6) and η(8) modes, the latter having metal atoms inserted in the carbonyl bond. Reorientation and diffusion of benzaldehyde is found to have low energy barriers. Aggregation of molecules in dimers bound by aryl C-H···O hydrogen bonds is investigated, and specific configurations are found to be up to 0.15 eV more favorable than optimally configured, separated adsorbates. The binding is significantly stronger than what is found for gas phase dimers, suggesting an enhancing effect of the metal interaction. 相似文献
974.
Stasyuk AJ Banasiewicz M Cyrański MK Gryko DT 《The Journal of organic chemistry》2012,77(13):5552-5558
A short and efficient route to a broad range of imidazo[1,2-a]pyridines from 2-aminopyridines and acetophenones is achieved by a tandem, one-pot process starting with an Ortoleva-King reaction. Optimal conditions for the first step were established after examining various reaction parameters (solvent, reagent ratios, and temperature). The conditions identified (1st step, neat, 2.3 equiv of 2-aminopyridine, 1.20 equiv of I(2), 4 h, 110 °C; 2nd step, NaOH(aq), 1 h, 100 °C) resulted in the formation of imidazo[1,2-a]pyridines in 40-60% yields. The synthesis is compatible with various functionalities (OH, NMe(2), Br, OMe). Products containing a 2-(2'-hydroxyphenyl) substituent undergo excited state intramolecular proton transfer (ESIPT) in nonpolar and polar-aprotic solvents. Although ESIPT-type emission in nonpolar solvents is weak, the Stokes shifts are very high (11000 cm(-1)). The comparison of the properties of six ESIPT-capable imidazo[1,2-a]pyridines shows the influence of various substituents on emission characteristics. All of them also display strong, solid-state emission in blue-green-yellow region. 2-Aryl-imidazo[1,2-a]pyridines not capable of ESIPT emit in the blue region, displaying high fluorescence quantum yield. 相似文献
975.
Dubrovskiy AV Markina NA Larock RC 《Combinatorial chemistry & high throughput screening》2012,15(6):451-472
The iodocyclization of functionally-substituted alkynes provides an excellent way to prepare a wide range of iodoheterocycles, which can then be readily elaborated through palladium-catalyzed Suzuki-Miyaura, Sonogashira, Heck, Hartwig-Buchwald, and carbonylation processes into libraries of medicinally relevant heterocycles. The synthesis of libraries of indoles, benzofurans, benzothiophenes, isocoumarins and pyrones, cyclic imidates, isoxazoles, furans using this approach is reviewed. This technology is very versatile, proceeds under mild reaction conditions in high yields, and tolerates considerable functionality. 相似文献
976.
Nagy AJ 《Combinatorial chemistry & high throughput screening》2012,15(2):189-198
Successful implementation of High throughput Experimentation (EE) tools has resulted in their increased acceptance as essential tools in chemical, petrochemical and polymer R&D laboratories. This article provides a number of concrete examples of EE systems, which have been designed and successfully implemented in studies, which focus on deriving reaction kinetic data. The implementation of high throughput EE tools for performing kinetic studies of both catalytic and non-catalytic systems results in a significantly faster acquisition of high-quality kinetic modeling data, required to quantitatively predict the behavior of complex, multistep reactions. 相似文献
977.
The interaction of two peptides with the α-hemolysin pore was studied in the presence of a MHz AC field. For an α-helical peptide the proportion of bumping events increased with increasing AC field whereas for a linear peptide with no dipole moment only small changes in the event profiles were observed. 相似文献
978.
Bouška M Dostál L Padělková Z Lyčka A Herres-Pawlis S Jurkschat K Jambor R 《Angewandte Chemie (International ed. in English)》2012,51(14):3478-3482
The step-wise oxidation of an organotin(I) compound with elemental tellurium gave a variety of unprecedented organotin tellurides containing tin atoms in the oxidation states +II and +IV. 相似文献
979.
Novák P Lishchynskyi A Grushin VV 《Angewandte Chemie (International ed. in English)》2012,51(31):7767-7770
Easy does it: Aryl boronic acids undergo smooth and selective trifluoromethylation with low-cost fluoroform-derived CuCF(3) in DMF in non-dried air. The reaction occurs under mild conditions (1?atm, room temperature), exhibits unprecedented functional-group tolerance, and affords trifluoromethylated aromatic compounds in up to 99?% yield. 相似文献
980.
The reaction of readily accessible 1,1-dialkylhydrazones with commercially available o-(trimethylsilyl)aryl triflates provides a direct one-step route to pharmaceutically important 1-alkylindazoles. The products are obtained in high yields by one-pot NCS-chlorination/aryne annulation or Ac(2)O-acylation/deprotection/aromatization protocols. 相似文献