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21.
Rebeca Infante Dr. Javier Nieto Prof. Dr. Celia Andrés 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(14):4375-4379
A highly efficient enantioselective addition of Me2Zn to α‐ketoesters, assisted by a chiral perhydro‐1,3‐benzoxazine ligand, is described. This novel catalytic system offers homogeneous elevated enantioselectivities in the preparation of α‐hydroxyesters that bear a quaternary stereocenter, with a minor dependence on electronic and steric effects when aromatic, heteroaromatic, or aliphatic α‐ketoesters are employed. The catalyst can be recovered and reused without loss of activity. 相似文献
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P.J. García Nieto J. Martínez Torres M. Araújo Fernández C. Ordóñez Galán 《Applied Mathematical Modelling》2012,36(12):6137-6145
Using advanced machine learning techniques as an alternative to conventional double-entry volume equations, a regression model of the inside-bark volume (dependent variable) for standing Eucalyptus globulus trunks (or main stems) has been built as a function of the following three independent variables: age, height and outside-bark diameter at breast height (DBH). The experimental observed data (age, height, outside-bark DBH and inside-bark volume) for 142 trees (E. globulus) were measured and a nonlinear model was built using a data-mining methodology based on support vector machines (SVM) and multilayer perceptron networks (MLP) for regression problems. Coefficients of determination and Furnival’s indices indicate the superiority of the SVM with a radial kernel over the allometric regression models and the MLP. 相似文献
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Daniel Romero Nieto Mikhail G. Zolotukhin Lioudmila Fomina Serguei Fomine 《Journal of Physical Organic Chemistry》2010,23(9):878-884
Energies of mono‐ and multiprotonation for 1,2,3‐indanetrione and ninhydrin in triflic acid (TFSA) media were estimated at PBE0/aug‐cc‐pvtz//6‐31+G** level of theory. The reactivity of formed intermediates in the reaction of aromatic electrophilic substitution has been studied at the same level of theory. It appears that the basicity of carbonyl groups in 1,2,3‐indanetrione is extremely low due to mutual influences of carbonyl groups. Carbonyl 2 is the least basic but the most reactive in accordance with experiment. Calculations demonstrated that monoprotonated intermediates are the principal reactive species in the reaction of hydroxyalkylation of 1,2,3‐indanetrione in TFSA. A new isomerization mechanism of 2,2‐diaryl‐1,3‐indanediones to 3‐(diarylmethylene)isobenzofuranones in TFSA media has been proposed. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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L. García-Río J.C. Mejuto M. Nieto J. Pérez-Juste M. Pérez-Lorenzo P. Rodríguez-Dafonte 《Supramolecular chemistry》2013,25(8):649-653
The influence of β-CD concentration on the acid hydrolysis of N-methyl-N-nitroso-p-toluenesulfonamide (MNTS) has been studied in the presence and absence of different alcohol concentrations. The rate of the denitrosation reaction in bulk water decrease as the β-CD concentration increases due to MNTS complexation in the CD cavity and the reaction taking place exclusively outside the cyclodextrin. Changes in this inhibition due to the presence of β-CD allow us to obtain the binding constants of different alcohols to the cyclodextrin. These binding constants are in very good agreement with those determined in the bibliography by other methods. 相似文献
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Marcel Scheepstra Dr. Lidia Nieto Dr. Anna K. H. Hirsch Dr. Sascha Fuchs Dr. Seppe Leysen Chan Vinh Lam Leslie in het Panhuis Prof. Dr. Constant A. A. van Boeckel Dr. Hans Wienk Prof. Dr. Rolf Boelens Dr. Christian Ottmann Dr. Lech‐Gustav Milroy Prof. Dr. Luc Brunsveld 《Angewandte Chemie (International ed. in English)》2014,53(25):6443-6448
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C. Magron Ph. Alfaurt B. Blank L. Daudin T. Eronen M. Gerbaux J. Giovinazzo D. Gorelov S. Grévy H. Guérin J. Hakala V. S. Kolhinen J. Koponen T. Kurtukian Nieto I. D. Moore H. Penttilä I. Pohjalainen J. Reinikainen M. Reponen S. Rinta-Antila M. Roche A. de Roubin N. Smirnova B. Thomas A. Voss L. Xayavong 《The European Physical Journal A - Hadrons and Nuclei》2017,53(4):77
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