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951.
Paolo Ceccherelli † Massimo Curini Maria Carla Marcotullio Francesco Epifano Ornelio Rosati 《合成通讯》2013,43(16):3057-3064
A mild and convenient oxidative Nef reaction using Oxone® (potassium hydrogen persulfate) is described. Following our procedure primary and secondary nitroalkanes generate carboxylic acids and ketones, respectively, both in good yields. 相似文献
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Giuseppe A. Consiglio Salvatore Failla Paolo Finocchiaro Kenneth I. Hardcastle 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):697-700
Williamson condensation of bis-o-hydroxy aryl phosphonates with dihaloalkylaryl derivatives yields the title compounds. They show interesting stereochemical aspects and some of them can be used in chiral recognitions and separations. 相似文献
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Grazia Bencivenni Dr. Diana Salazar Illera Dr. Maria Moccia Prof. K. N. Houk Dr. Joseph A. Izzo Dr. Johanna Novacek Prof. Paolo Grieco Prof. Mathew J. Vetticatt Prof. Mario Waser Prof. Mauro F. A. Adamo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(44):11352-11366
Chiral phase-transfer catalysis provides high level of enantiocontrol, however no experimental data showed the interaction of catalysts and substrates. 1H NMR titration was carried out on Cinchona and Maruoka ammonium bromides vs. nitro, carbonyl, heterocycles, and N−F containing compounds. It was found that neutral organic species and quaternary ammonium salts interacted via an ensemble of catalyst +N−C−H and (sp2)C−H, specific for each substrate studied. The correspondent BArF salts interacted with carbonyls via a diverse set of +N−C−H and (sp2)C−H compared to bromides. This data suggests that BArF ammonium salts may display a different enantioselectivity profile. Although not providing quantitative data for the affinity constants, the data reported proofs that chiral ammonium salts coordinate with substrates, prior to transition state, through specific C−H positions in their structures, providing a new rational to rationalize the origin of enantioselectivity in their catalyses. 相似文献
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Raffaella Calabrese Johan A. Elkink Paolo S. Giudici 《The Journal of the Operational Research Society》2017,68(12):1503-1511
The recent European sovereign debt crisis clearly illustrates the importance of measuring the contagion effects of bank failures. Indeed, to better understand and monitor contagion risk, the European Central Bank has assumed the supervision of the largest banks in each of the member states. We propose a measure of contagion risk based on the spatial autocorrelation parameter of a binary spatial autoregressive model. Using different specifications of the interbank connectivity matrix, we estimate the contagion parameter for banks within the Eurozone, between 1996 and 2012. We provide evidence of high levels of systemic risk due to contagion during the European sovereign debt crisis. 相似文献
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Riccardo Falciai Francesco Baldini Franco Cosi Paolo Bechi Filippo Pucciani 《Fiber and Integrated Optics》2013,32(2):215-222
Abstract A portable optical-fiber sensor for ambulatory assessment of the enterogastric reflux, based on the optical properties of the bile, was developed. It makes use of two light-emitting diodes and of an appropriate electronic circuit that processes the signals and provides the readout on a display. A suitable probe for in vivo measurements was designed. Plastic fiber bundles are used in order to obtain probe flexibility and low price. In vivo measurements performed on different patients show the superiority of this technique over existing methods. 相似文献
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