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81.
82.
Itka Bkouche-Waksman A. Kvick Marie Laure Boillot Olivier Kahn 《Journal of chemical crystallography》1991,21(5):595-600
The title compound has been synthesized and its crystal structure has been solved at room temperature. It crystallizes in the triclinic system, space groupP, witha=7.853(1) Å,b=10.177(1) Å,c=13.651(4) Å,=74.57(1)°,=88.49(1)°, =80.675(4)°, andZ=2. The structure consists of isolated [Cu(bipy)2N3]+ cations (bipy=2,2-bipyridine) and perchlorate anions. The metallic cation environment has a distorted trigonal-bipyramidal geometry. The EPR spectrum is rhombic, which indicates that the distortion with respect to the perfect trigonal bipyramid is sufficiently pronounced to mixz
2- andx
2–y
2-type orbitals in the ground state. The temperature dependence of the molar magnetic susceptibility has been investigated in the 300-2.2 K temperature range. 相似文献
83.
84.
Daiguebonne C Kerbellec N Guillou O Bünzli JC Gumy F Catala L Mallah T Audebrand N Gérault Y Bernot K Calvez G 《Inorganic chemistry》2008,47(9):3700-3708
Reaction in water between rare earth ions (Ln = Y, La-Tm, except Pm) and the sodium salt of terephthalic acid leads to a family of lanthanide-based coordination polymers of general formula [Ln2(C8H4O4)3(H2O)4] n with Ln = La-Tm or Y. The isostructurality of the compounds with the previously reported Tb-containing polymer is ascertained on the basis of their X-ray powder diffraction diagrams. The coordination water molecules can be reversibly removed without destroying the crystal structure for compounds involving one of the lighter lanthanide ions (La-Eu). For compounds involving one of the heavier lanthanide ions (Tb-Tm) or yttrium, a structural change occurs during the drying process. X-ray diffraction data show this new anhydrous phase corresponding to the linking of pairs of Er(III) ions through mu-carboxylate bridges. Porosity profiles calculated for the anhydrous phases of Tb(III) and Er(III) show the presence of channels with very small sections. The luminescent properties of all the compounds have been recorded and the two most luminescent polymers, namely, the europium- and the terbium-containing ones, have been studied in more detail. Tb(III)-containing compounds display large quantum yields, up to 43%. Polyvinylpyrrolidone nanoparticles doped with [Ln2(C8H4O4)3(H2O)4] n (Ln = Eu, Tb, Er) have also been synthesized and characterized. The encapsulation of the coordination polymers results in somewhat reduced luminescence intensities and lifetime, but the nanoparticles can be dispersed in water and remain unchanged in this medium for more than 20 h. 相似文献
85.
Dr. Sarah Desmons Yu Zhou Dr. Dan Zhang Dr. Carlos Jarava-Barrera Dr. Anaïs Coffinet Dr. Antoine Simonneau Dr. Laure Vendier Prof. Dr. Gen Luo Dr. Sébastien Bontemps 《European journal of organic chemistry》2023,26(30):e202300525
The hydroboration of CO2 into bis(boryl)acetal (BBA) compounds is an important transformation, since it enabled to selectively reduce CO2 by 4e- and to subsequently use the BBA compounds as C1 and Cn sources. However, the influence of the nature of the boryl moieties on the reactivity of BBA compounds has not been evaluated so far. In the present study, four BBA compounds – including two new ones – were reacted with 2,6-diisopropylaniline to afford the expected imine. Significant differences in the rate of the reaction from minutes to weeks have been observed depending on the BBA used, showing the importance of the nature of the boryl moieties. Theoretical investigations enabled to propose a mechanism involving the addition of the aniline to the BBA as the rate-determining step and to determine that the steric hindrance of the BBA compounds is the main factor driving the rate of this condensation reaction. 相似文献
86.
Synthesis and Thermophysical Properties of Ether‐Functionalized Sulfonium Ionic Liquids as Potential Electrolytes for Electrochemical Applications
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Dr. Erwan Coadou Dr. Peter Goodrich Alex R. Neale Dr. Laure Timperman Prof. Christopher Hardacre Dr. Johan Jacquemin Prof. Mérièm Anouti 《Chemphyschem》2016,17(23):3992-4002
During this work, a novel series of hydrophobic room temperature ionic liquids (ILs) based on five ether functionalized sulfonium cations bearing the bis{(trifluoromethyl)sulfonyl}imide, [NTf2]? anion were synthesized and characterized. Their physicochemical properties, such as density, viscosity and ionic conductivity, electrochemical window, along with thermal properties including phase transition behavior and decomposition temperature, have been measured. All of these ILs showed large liquid range temperature, low viscosity, and good conductivity. Additionally, by combining DFT calculations along with electrochemical characterization it appears that these novel ILs show good electrochemical stability windows, suitable for the potential application as electrolyte materials in electrochemical energy storage devices. 相似文献
87.
A new PN2S ligand, N-[2-(diphenylphosphino)phenyl]-2-[(S-trityl)acetylamino]ethanamide [Ph-P(Ph2)N2S(Trt)], was synthesised and reacted with ReV precursors. The reaction of both tritylated and detritylated ligands with ReOCl3(PPh3)2 gave the same expected neutral complex [ReO{Ph-P(Ph2)N2S}] (4) in good yield. An unexpected neutral and diamagnetic species, [ReN{Ph-P(Ph2)N2S(Trt)}] (5), has been isolated during the complexation of the tritylated ligand with ReNCl2(PPh3)2. The complexes, characterized by classical spectroscopic methods and X-ray analysis for 4, are the first examples of neutral semi-rigid-PN2S rhenium(V) complexes. 相似文献
88.
89.
Clifford MN Lopez V Poquet L Williamson G Kuhnert N 《Rapid communications in mass spectrometry : RCM》2007,21(13):2014-2018
We report a systematic investigation of the effects and structural requirements for ion suppression in negative ion mode electrospray ionisation mass spectrometry of a series of carboxylic acids and present a structural model rationalising ion suppression effects. 相似文献
90.