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91.
Ju‐You Lu Hong Wan Jianwei Zhang Zhixuan Wang Yang Li Yongmei Du Chunying Li Prof. Zhao‐Tie Liu Prof. Zhong‐Wen Liu Prof. Jian Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17542-17546
A palladium‐catalyzed direct C‐arylation reaction of readily available cage carboranyllithium reagents with aryl halides has been developed for the first time. This method is applicable to a wide range of aryl halide substrates including aryl iodides, aryl bromides, and heteroaromatic halides. 相似文献
92.
93.
Shuang-Shuang Yang Ming-Jiang Xie Yu Shen Yong-Zheng Wang Xue-Feng Guo Bin Shen 《中国化学快报》2016,27(4):507-510
Chemical doping of nickel hydroxide with other cations(e.g. Al~(3+)) is an efficient way to enhance its electrochemical capacitive performances. Herein, a simple cation–anion(Ni~(2+)and AlO_2) double hydrolysis method was developed toward the synthesis of nickel–aluminum(Ni–Al) composite hydroxides. The obtained composite hydroxides possesses a porous structure, large surface area(121 m~2/g) and homogeneous element distribution. The electrochemical test shows that the obtained composite hydroxides exhibits a superior supercapacitive performances(specific capacitance of 1670F/g and rate capability of 87% from 0.5 A/g to 20 A/g) to doping-free nickel hydroxide(specific capacitance of 1227 F/g and rate capability of 47% from 0.5 A/g to 20 A/g). Moreover, the galvanostatic charge/discharge test displays that after 2000 cycles at large current density of 10 A/g, the composite hydroxides achieves a high capacitance retention of 98%, indicative of an excellent electrochemical cycleability. 相似文献
94.
95.
Inside Back Cover: Stepwise Assembly of MII7 Clusters Revealed by Mass Spectrometry,EXAFS, and Crystallography (Chem. Eur. J. 51/2016) 下载免费PDF全文
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97.
Rajangam Vinodh Mani Ganesh Mei Mei Peng Aziz Abidov Muthiahpillai Palanichamy Wang Seog Cha Hyun-Tae Jang 《高分子科学》2015,33(2):224-235
Microporous hypercross-linked conjugated quinonoid chromophores represent a novel class of amorphous polymers, synthesized by the reaction of anthracene with dimethoxy methane in the presence of FeCl3 catalyst. Their N2 adsorption isotherms confirm their microporous nature. Diffuse reflectance UV-Visible(DRS UV-Vis) spectroscopy confirms their matrix built with the conjugated quinonoids by their broad light absorption characteristics extending from 1000 nm to 200 nm with the absorbance maximum close to 400 nm. The catalyst cross-linked anthracene with ―CH2― bridges and subsequently dehydrogenating them to form quinonoids. Their Fourier transform infrared(FTIR) spectra showed their characteristic quinonoid vibrations between 1600 and 1700 cm-1. The synthesis of polymers was carried out at 30, 40, 50, 60, 70 and 80 ℃, but the quinonoid content of the polymer obtained at 80 ℃ was higher than that of the others. Their scanning electron microscopy(SEM) images showed microspheres of 1 to 5 μm size built with tiny particles. Their surfaces were not smooth. The polymer synthesized at 80 ℃ showed 5.1 wt% CO2 sorption at 25 ℃ and 0.1 MPa, but when it was recross-linked, the CO2 sorption increased to 8 wt%. Hence, hypercross-linked conjugated quinonoid chromophores of anthracene are good for sorption of CO2. 相似文献
98.
Water‐Soluble Luminescent Hybrid Composites Consisting of Oligosilsesquioxanes and Lanthanide Complexes and their Sensing Ability for Cu2+ 下载免费PDF全文
Qianqian Xu Dr. Zhiqiang Li Prof. Dr. Huanrong Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):3037-3043
Water‐soluble hybrid composites with great potential for selective and sensitive sensing and that are obtained through simple, rapid, and environmentally friendly methods are highly desirable and remain a challenging task. Herein, we present luminescent hybrid composites that were realized by linking Na3[Ln(dpa)3] (dpa=2,6‐pyridinedicarboxylic acid) to octa‐amino functionalized polyhedral oligomeric silsesquioxane (POSS‐NH2) through hydrogen‐bonding interactions between the oxygen atoms of the carboxylate groups of dpa and the hydrogen‐bond‐donor amino groups. The resulting hybrid composites Ln(dpa)3@POSS‐NH2 are highly soluble in aqueous solutions and the quantum yield of Eu(dpa)3@POSS‐NH2 is as high as 56.5 % or 46.3 % in the solid state and in aqueous solution, respectively, as determined by using the integrating sphere method. The novel water‐soluble luminescent hybrid composites exhibit high thermal and photostability, and the emitted colors of the resulting hybrid composite can be finely tuned by changing the Eu3+/Tb3+ ratio. Interestingly, Eu(dpa)3@POSS‐NH2 hybrid composites exhibited an effective switch‐off fluorescence response to Cu2+ over other common metal ions in aqueous media. 相似文献
99.
Niklas Rinn Dr. Jens P. Eußner Willy Kaschuba Dr. Xiulan Xie Prof. Dr. Stefanie Dehnen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):3094-3104
Reactions of R1SnCl3 (R1=CMe2CH2C(O)Me) with (SiMe3)2Se yield a series of organo‐functionalized tin selenide clusters, [(SnR1)2SeCl4] ( 1 ), [(SnR1)2Se2Cl2] ( 2 ), [(SnR1)3Se4Cl] ( 3 ), and [(SnR1)4Se6] ( 4 ), depending on the solvent and ratio of the reactants used. NMR experiments clearly suggest a stepwise formation of 1 through 4 by subsequent condensation steps with the concomitant release of Me3SiCl. Furthermore, addition of hydrazines to the keto‐functionalized clusters leads to the formation of hydrazone derivatives, [(Sn2(μ‐R3)(μ‐Se)Cl4] ( 5 , R3=[CMe2CH2CMe(NH)]2), [(SnR2)3Se4Cl] ( 6 , R2=CMe2CH2C(NNH2)Me), [(SnR4)3Se4][SnCl3] ( 7 , R4=CMe2CH2C(NNHPh)Me), [(SnR2)4Se6] ( 8 ), and [(SnR4)4Se6] ( 9 ). Upon treatment of 4 with [Cu(PPh3)3Cl] and excess (SiMe3)2Se, the cluster fragments to form [(R1Sn)2Se2(CuPPh3)2Se2] ( 10 ), the first discrete Sn/Se/Cu cluster compound reported in the literature. The derivatization reactions indicate fundamental differences between organotin sulfide and organotin selenide chemistry. 相似文献
100.
Theoretical investigations on the insertion reaction mechanisms of three- membered-ring silylenoid H2 Si Li F with GeH 3R(R = F, OH, NH2) have been systematically carried out by combined density functional theory(DFT) and ab initio quantum chemical calculations. The geometries of all stationary points for these reactions were optimized using the B3 LYP method and then the QCISD method was used to calculate the single-point energies. The calculated results indicate that, there are one precursor complex(Q), one transition state(TS), and one intermediate(IM) which connect the reactants and the products along the potential energy surface. The insertion reactions of three-membered-ring silylenoid with Ge H3 R proceed in a concerted manner, forming H2RSi-Ge H3 and Li F. The calculated potential energy barriers of the three reactions are 29.17, 30.90, and 54.07 k J/mol, and the reaction energies for the three reactions are –127.05, –116.91, and –103.31 k J/mol, respectively. The insertion reactions in solvents are similar to those in vacuum. Under the same situation, the insertion reactions should occur easily in the following order: GeH 3-F GeH 3-OH GeH 3-NH2. The elucidations of the mechanism of these insertion reactions provided a new mode of silicon-germanium bond formation. 相似文献