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1.
Dr. Yoko Hasegawa Dr. Thomas Cantin Dr. Jonathan Decaens Dr. Samuel Couve-Bonnaire Prof. Dr. André B. Charette Prof. Dr. Thomas Poisson Prof. Dr. Philippe Jubault 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(47):e202201438
The first diastereo- and enantioselective cyclopropanation reactions of electron-deficient allenes with donor-acceptor and diacceptor diazo reagents are described. The desired enantioenriched alkylidenecyclopropanes (ACPs) were obtained in high yields with high diastereo- and enantioselectivities in the presence of Rh2((S)-TCPTAD)4 or Rh2((R)-BTPCP)4 catalysts (up to 95 % yield, >95 : 5 d.r. and 99 : 1 e.r.). This methodology gave a direct access to ACPs bearing multiple electron-deficient substituents and allows to further expand the availability of ACPs chemistry. Interestingly, during the examination of the scope of this reaction, the asymmetric intramolecular C−H insertion reaction into tert-butyl group was observed as a side reaction with up to 94 : 6 e.r. 相似文献
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Queueing Systems - We study a quantum switch that distributes tripartite entangled states to sets of users. The entanglement switching process requires two steps: First, each user attempts to... 相似文献
3.
Michele Arcangelo Quinto Juan Manuel Monti Mario Enrique Alcocer Avila Philippe F. Weck Omar Ariel Fojón Roberto Daniel Rivarola Christophe Champion 《X射线光谱测定》2020,49(1):95-98
The present work focuses on studying the contribution of the Auger electron emission in proton-induced interactions in biological matter. The Monte Carlo track-structure code, TILDA-V, was then used for modeling the protons beams of 10 keV to 100 MeV in biological matter, namely, water vapor and hydrated DNA. The main ionizing processes are described by means of an extensive set of ab initio differential and total cross sections computed within a quantum-mechanical CDW-EIS approximation. 相似文献
4.
Philippe Lewalle Sreenath K. Manikandan Cyril Elouard Andrew N. Jordan 《Contemporary Physics》2020,61(1):26-50
We review the continuous monitoring of a qubit through its spontaneous emission, at an introductory level. Contemporary experiments have been able to collect the fluorescence of an artificial atom in a cavity and transmission line, and then make measurements of that emission to obtain diffusive quantum trajectories in the qubit's state. We give a straightforward theoretical overview of such scenarios, using a framework based on Kraus operators derived from a Bayesian update concept; we apply this flexible framework across common types of measurements including photodetection, homodyne, and heterodyne monitoring and illustrate its equivalence to the stochastic master equation formalism throughout. Special emphasis is given to homodyne (phase-sensitive) monitoring of fluorescence. The examples we develop are used to illustrate basic methods in quantum trajectories, but also to introduce some more advanced topics of contemporary interest, including the arrow of time in quantum measurement, and trajectories following optimal measurement records derived from a variational principle. The derivations we perform lead directly from the development of a simple model to an understanding of recent experimental results. 相似文献
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“(Diphosphine)Nickel”‐Catalyzed Negishi Cross‐Coupling: An Experimental and Theoretical Study 下载免费PDF全文
Dr. Emmanuel Nicolas Alexia Ohleier Florian D'Accriscio Dr. Anne‐Frédérique Pécharman Dr. Matthieu Demange Dr. Philippe Ribagnac Dr. Jorge Ballester Dr. Corinne Gosmini Dr. Nicolas Mézailles 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7690-7694
The use of a strongly donating “(bis‐dialkylphosphine)Ni” fragment promotes the catalytic coupling of a large range of ArCl and ArZnCl derivatives under mild conditions. Stoichiometric mechanistic investigations and DFT calculations prove that a Ni0/NiII cycle is operative in this system. 相似文献
7.
Florence Drui Emmanuel Franck Philippe Helluy Laurent Navoret 《Comptes Rendus Mecanique》2019,347(3):259-269
The over-relaxation approach is an alternative to the Jin–Xin relaxation method in order to apply the equilibrium source term in a more precise way. This is also a key ingredient of the lattice Boltzmann method for achieving second-order accuracy. In this work, we provide an analysis of the over-relaxation kinetic scheme. We compute its equivalent equation, which is particularly useful for devising stable boundary conditions for the hidden kinetic variables. 相似文献
8.
Lotfi Boudjema Dr. Jérôme Long Dr. Fabrice Salles Prof. Joulia Larionova Dr. Yannick Guari Prof. Philippe Trens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(2):479-484
Porous coordination polymers are molecule-based materials presenting a high degree of tunability, which offer many advantages for targeted applications over conventional inorganic materials. This work demonstrates that the hydrophilic/hydrophobic character of Prussian blue analogues having a lipophilic feature may be tuned to optimize the gas adsorption properties. The role of the coordinatively unsaturated metal sites is emphasized through a combination of theoretical and experimental study of water, ethanol, and n-hexane adsorption. 相似文献
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Synthesis of polyphosphodiesters by ring‐opening polymerization of cyclic phosphates bearing allyl phosphoester protecting groups 下载免费PDF全文
Benoït Clément Daniel G. Molin Christine Jérôme Philippe Lecomte 《Journal of polymer science. Part A, Polymer chemistry》2015,53(22):2642-2648
The allyl phosphoester group is shown to be a protecting group for the synthesis of anionic polyphosphodiesters. Our strategy relies on the synthesis of a cyclic phosphate monomer bearing a pendant allyl phosphoester group, its easy purification by fractional distillation, its organocatalyzed ring‐opening polymerization by 1,8‐diazobicyclo[5.4.0]undec‐7‐ene (DBU) and 1‐[3,5‐bis(trifluoromethyl)phenyl]‐3‐cyclohexyl‐thiourea (TU). Finally, the deprotection of the allyl phosphoester group is carried out by reaction with sodium benzenethiolate in the absence of any detectable degradation. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2642–2648 相似文献