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941.
轮烷类互锁分子因其多样的结构和性质,多年来一直是超分子化学领域的一个热点.综述了近年来轮烷类化合物的合成及制备方法,包括用传统的模板法(引入氢键、疏水作用、静电效应、配位和离子诱导等超分子作用)制备轮烷类化合物.除此之外,还介绍了利用“Click”化学、“穿线-收缩”、“穿线-膨胀”、自排序组织和自由基识别等新的合成手段来制备这类化合物. 相似文献
942.
A method for preparing multisubstituted N-(tosylamino)pyrrole derivatives through AuCl3-catalyzed cycloisomerization of the β-alkynyl hydrazone compounds was described. The reaction could be carried out in one pot from the β-ketoesters to give the cyclized products in moderate to excellent yields with low catalyst loadings. 相似文献
943.
Yin-Di Zhu Jing-Yi Zhang Peng-Fei Li Hai-Feng Wu Nai-Liang Zhu Hai Jiang 《Natural product research》2016,30(9):1075-1080
Two new abietane diterpenoid glycosides, named clinopoditerpenes B (1) and C (2), were isolated from Clinopodium chinese. The structures of the new compounds were determined on the basis of extensive spectral analysis. Compound 1 exhibited cardioprotective effect against H2O2-induced apoptosis in H9c2 cells. 相似文献
944.
Ji Jinfeng Song Guangliang Cai Xiao Hu Jinyang Feng Liang Zhu Hongjun 《Research on Chemical Intermediates》2016,42(6):5597-5605
Research on Chemical Intermediates - A spirooxazine derivative 1,3-dihydro-1,3,3-trimethyl-spiro[2-H-indole-2-2′-[2H-1,4] oxazino [2,3-f] [1, 10] phenanthroline] (compound 1) was explored as... 相似文献
945.
Orientation Angle of Molecules at Hexadecane-Water Interface Studied with Total Internal Reflection Second Harmonic Generation 下载免费PDF全文
The orientation angle is an important parameter that reflects the structure of molecules at interfaces. In order to obtain this parameter, second order nonlinear spectroscopic techniques including second harmonic generation (SHG) and sum frequency generation-vibrational spectroscopy (SFG-VS) have been successfully applied through analysis of the nonlinear signal from various polarizations. In some SHG and SFG-VS experiments, total internal reflection (TIR) configuration has been adopted to get enhanced signals. However, the reports on the detailed procedure of the polarization analysis and the calculation of the orientation angle of interfacial molecules under TIR configuration are still very few. In this paper, we measured the orientation angles of two molecules at the hexadecane-water interface under TIR and Non-TIR experimental configurations. The results measured from polarization analysis in TIR configuration consist with those obtained from Non-TIR configuration. This work demonstrates the feasibility and accuracy of polarization analysis in the determination of the orientation angle of molecules at the interfaces under TIR-SHG configuration. 相似文献
946.
pH Dependent Synthesis of NdIII Coordination Compounds Based on Bifunctional 5‐(4‐Pyridyl)tetrazole‐2‐acetic Acid 下载免费PDF全文
Meng Jie Cao Yue Kang Li Peng Peng Sun Chen Yi Zhang Jue Wang Qiao Yun Li Gao Wen Yang 《无机化学与普通化学杂志》2016,642(21):1218-1221
The NdIII coordination compounds [Nd(4‐pytza)3(H2O)2] · 2H2O ( 1 ) and [Nd(4‐pytza)2(H2O)4]Cl · 2H2O ( 2 ) [H4‐pytza = 5‐(4‐pyridyl)tetrazole‐2‐acetic acid] were synthesized by reactions of K4‐pytza and NdCl3 · 6H2O at different pH values. Single crystal X‐ray diffraction analysis reveals that 4‐pytza ligands in 1 in a μ1,3‐COO syn‐syn or μ1,1,3‐COO bridging mode coordinate to two central NdIII atoms to display a dinuclear unit, which is connected by one of these 4‐pytza ligands acting in end‐to‐end bridging mode to form a 1D ladder‐like chain. Different from 1 , each 4‐pytza in 2 with a μ1,3‐COO syn‐anti bridging mode coordinates to two NdIII atoms to display a 1D zigzag chain. Furthermore, the luminescence properties of 1 and 2 were investigated at room temperature in the solid state. 相似文献
947.
采用基于密度泛函理论(DFT)的Dmol3程序系统研究了O原子与O2在 Au19与Au20团簇上的吸附反应行为. 结果表明: O在Au19团簇顶端洞位上的吸附较Au20强; 在侧桥位吸附强度相近. O与O2在带负电Au团簇上吸附较强, 在正电团簇吸附较弱. 从O―O键长看, 当金团簇带负电时, O―O键长较长, 中性团簇次之, 正电团簇中O―O键长较短, 因而O2活化程度依次减弱. 电荷布居分析表明, Au团簇带负电时, O与O2得电子数较中性团簇多, 而团簇带正电时, 得电子数较少. 差分电荷密度(CDD)表明, O2与Au团簇作用时, 金团簇失电子, O2的π*轨道得电子, 使O―O键活化. O2在Au19-团簇上解离反应活化能为1.33 eV, 较中性团簇低0.53 eV; 而在Au19+上活化能为2.27 eV, 较中性团簇高0.41 eV, 这与O2在不同电性Au19团簇O―O键活化规律相一致. 相似文献
948.
A novel hydrated cobalt tetraborate complex NH4[Co(NH3)5(H2O)][B4O5(OH)4]2·6H2O, was synthesized by the reaction of NH4‐borate aqueous with CoCl2 and its structure was determined by single crystal X‐ray diffraction. The crystal system of this complex is orthorhombic, the space group is Pnma, and the unit cell parameters are a=1.2901(2) nm, b=1.6817(3) nm, c=1.1368(2) nm, α=β=γ=90°, V=2.4742(8) nm3, and Z=4. This compound contains infinite borate layers constructed from [B4O5(OH)4]2? units via hydrogen bonds. The adjacent polyborate anion layers are further linked together with the octahedral [Co(NH3)5(H2O)]3+ groups through hydrogen bonds to form 3D framework. The groups and guest water molecules are deposited in the empty space of this framework and interact with the layers by extensive hydrogen bonds. Infrared and Raman spectra (4000–400 cm?1) of NH4[Co(NH3)5(H2O)][B4O5(OH)4]2·6H2O were recorded at room temperature and analyzed. Fundamental vibrational modes were identified and band assignments were made. The middle band observed at 575 cm?1 in Raman spectrum is the pulse vibration of [B4O5(OH)4]2?. 相似文献
949.
小分子铱配合物及其电致发光 总被引:1,自引:0,他引:1
由于磷光金属配合物可以同时利用单线态和三线态激子发光,使有机电致发光器件的理论内量子效率达到100%,突破了25%的极限。因而以磷光金属配合物为发光材料制成的器件备受关注。在这些金属配合物中,铱配合物由于具有较强的发光特性、发光波长可调性、较好的热稳定性和电化学稳定性以及能够形成便于蒸镀的中性分子,而成为最有应用潜力的电致磷光材料。本文综述了近几年铱配合物磷光材料在分子设计与合成方法、发光机理及器件构筑等方面的研究进展。特别介绍与讨论了磷光铱配合物的两种发光机理,即基于同配体铱配合物或异配体铱配合物的主配体到中心金属离子的电荷转移三线态(3MLCT)发射和基于异配体铱配合物的辅助配体三线态(3LC)发射。根据反应条件的差异,归纳总结了合成铱配合物常用的4种方法以及合成fac式和mer式的铱配合物的方法。还根据材料的发光颜色及其电致发光的不同,对磷光铱配合物材料进行了分类与讨论。此外,简要介绍了用于器件制作的主体材料。最后,展望了金属有机配合物电致磷光材料的发展前景,并提出了今后磷光材料的发展方向。 相似文献
950.
This work described a sensitive method for determination of metoprolol in rabbit plasma.The method involved purification by ultrafiltration,derivatization with fluorescein isothiocyanate,determination by capillary electrophoresis(CE) coupled with laser-induced fluorescence(LIF) detector.Other components in plasma including a variety of amino acids and proteins did not interfere with the determination of metoprolol in experimental condition.The assay had a wide range(2.0-500 ng/mL) of linearity and a detection limit of 0.8 ng/mL.The intra- and inter-day precisions were satisfactory with relative standard deviation(RSD) less than 10.0%and accuracy within 10.0%.This method was successfully applied to pharmacokinetic study of metoprolol in rabbit blood. 相似文献