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51.
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Stereoselective Preparation of Polyfunctional Alkenylindium(III) Halides and Their Cross‐Coupling with Unsaturated Halides 下载免费PDF全文
Zhi‐Liang Shen Prof. Dr. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7061-7065
The direct insertion of indium powder to cycloalkenyl iodides in the presence of LiCl in THF allows the preparation of new highly functionalized cycloalkenylindium(III) derivatives. In addition, we discovered that, in contrast to many metal insertions to alkenyl iodides which proceed with a loss of stereochemistry, the insertion of In/LiCl to stereodefined (Z)‐ and (E)‐styryl iodides in THF proceeded with high retention of stereochemistry. After a palladium‐catalyzed cross‐coupling, various polyfunctionalized (Z)‐ and (E)‐stilbenes were obtained with high stereoselectivity. 相似文献
53.
The Effect of the Spacer of Bis(biurea) Ligands on the Structure of A2L3‐type (A=anion) Phosphate Complexes 下载免费PDF全文
Prof. Biao Wu Dr. Shaoguang Li Prof. Yibo Lei Prof. Huaiming Hu Dr. Nader de Sousa Amadeu Prof. Dr. Christoph Janiak Dr. Jennifer S. Mathieson Dr. De‐Liang Long Prof. Leroy Cronin Prof. Xiao‐Juan Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2588-2593
By tuning the length and rigidity of the spacer of bis(biurea) ligands L, three structural motifs of the A2L3 complexes (A represents anion, here orthophosphate PO43?), namely helicate, mesocate, and mono‐bridged motif, have been assembled by coordination of the ligand to phosphate anion. Crystal structure analysis indicated that in the three complexes, each of the phosphate ions is coordinated by twelve hydrogen bonds from six surrounding urea groups. The anion coordination properties in solution have also been studied. The results further demonstrate the coordination behavior of phosphate ion, which shows strong tendency for coordination saturation and geometrical preference, thus allowing for the assembly of novel anion coordination‐based structures as in transition‐metal complexes. 相似文献
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Liang Wanjun Liu Zhengqing Li Dan Wu Xiaoping Liu Shaopu He Youqiu 《Mikrochimica acta》2015,182(1-2):297-306
Microchimica Acta - We describe a novel fluorescent bioprobe for the sensitive and selective detection of double-stranded DNA (dsDNA). It consists of quantum dots (Q-dots) whose fluorescence is... 相似文献
56.
Modified Lagrangian vortex method with improved boundary conditions for water waves past a thin bottom‐standing barrier 下载免费PDF全文
Herein, the modified Lagrangian vortex method (LVM), a hybrid analytical‐numerical algorithm per se, is devised to simulate the process of vortex formation and shedding from the sharp edge of a zero‐thickness vertical plate under linear water‐wave attack. Application of the Helmholtz decomposition facilitates a convenient switch between the inviscid‐ and viscous‐flow models, thereby enabling easy incorporation of vorticity effects into the potential‐flow calculations for the viscous‐dominated region. In evaluating the potential‐flow component, making good use of the quickly convergent technique with singular basis functions, correctly capturing the singular behavior in velocity fields near the tip of the plate, leads to a considerable reduction of computational burdens and to 12‐decimal‐place accuracy. The viscous correction is carried out via the meshless LVM with improved boundary conditions. Comparisons with previously published results show good agreement. Simulations of vortex generation and evolution illuminate the ability of the present method, and provide a supplement to pertinent experimental works. The hybrid scheme proposed herein allows flexibility for the former LVM and convenience in the code development. Such a compromise fits particularly well for the high‐resolution modeling of sharp‐edged vortex shedding without heavy numerical developments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Target and non‐target identification of chemical components in Lamiophlomis rotata by liquid chromatography/quadrupole time‐of‐flight mass spectrometry using a three‐step protocol 下载免费PDF全文
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In the presence of the inexpensive and non‐toxic polymethylhydrosiloxane, the combination of copper(II) acetate and a chiral diphosphine displayed high catalytic efficiency in the asymmetric hydrosilylation of a series of aromatic ketones in air atmosphere and at room temperature. (R)‐1‐Arylethanols were obtained with up to 99% yield and 93% enantiomeric excess. Meanwhile, the electron effect and steric hindrance of substituents on the aromatic ring had an interesting influence on both the yields and enantioselectivities. Furthermore, a possible mechanism was presented to explain the influence of some key factors on the reaction. 相似文献
60.
Guanfeng Lin Tiancai Liu Jingyuan Hou Zhiqi Ren Jianwei Zhou Qianni Liang Zhenhua Chen Wenqi Dong Yingsong Wu 《Journal of fluorescence》2015,25(2):361-367
A sensitive, rapid and novel measurement method for cytokeratin 19 fragment (CYFRA 21–1) in human serum by magnetic particle-based time-resolved fluoroimmunoassay (TRFIA) is described. Built on a sandwich-type immunoassay format, analytes in samples were captured by one monoclonal antibody coating onto the surface of magnetic beads and “sandwiched” by another monoclonal antibody labeled with europium chelates. The coefficient variations of the method were lower than 7 %, and the recoveries were in the range of 90–110 % for serum samples. The lower limit of quantitation of the present method for CYFRA 21–1 was 0.78 ng/ml. The correlation coefficient of CYFRA 21–1 values obtained by our novel TRFIA and CLIA was 0.980. The present novel TRFIA demonstrated high sensitivity, wider effective detection range and excellent reproducibility for determination of CYFRA 21–1 can be useful for early screening and prognosis evaluation of patients with non-small cell lung cancer. 相似文献