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In‐Depth Understanding of the Chemical Properties of Rarely Explored Carbide Cluster Metallofullerenes: A Case Study of Sc2C2@C3v(8)‐C82 that Reveals a General Rule 下载免费PDF全文
Wenting Cai Muqing Chen Lipiao Bao Dr. Yunpeng Xie Prof. Dr. Takeshi Akasaka Prof. Dr. Xing Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3449-3454
The chemical properties of carbide‐cluster metallofullerenes (CCMFs) remain largely unexplored, although several new members of CCMFs have been discovered recently. Herein, we report the reaction between Sc2C2@C3v(8)‐C82, which is viewed as a prototypical CCMF because of its high abundance, and 3‐triphenylmethyl‐5‐oxazolidinone ( 1 ) to afford the corresponding pyrrolidino derivative Sc2C2@C3v(8)‐C82(CH2)2NTrt ( 2 ; Trt=triphenylmethyl). Single‐crystal X‐ray crystallography studies of 2 revealed that the reaction takes place at a [6,6]‐bond junction, which is directly over the encapsulated C2 unit and is far from either of the two scandium atoms. On the basis of theoretical calculations and by considering previously reports, we have found that a hexagonal carbon ring on the cage of Sc2C2@C3v(8)‐C82 is highly reactive toward different reagents due to the overlap of high p‐orbital axis vector (POAV) angles and large LUMO coefficients. We propose that this highly concentrated area of reactivity is generated by the encapsulation of the Sc2C2 cluster because this region is absent from the empty fullerene C3v(8)‐C82. Moreover, the absorption and electrochemical results confirm that derivative 2 is more stable than pristine Sc2C2@C3v(8)‐C82, thus illuminating its potential applications. 相似文献
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Characterization of a Novel Intrinsic Luminescent Room‐Temperature Ionic Liquid Based on [P6,6,6,14][ANS] 下载免费PDF全文
Joana M. Delgado Dr. Anabela Raymundo Dr. Márcia Vilarigues Dr. Luís C. Branco Dr. César A. T. Laia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):726-732
Intrinsically luminescent room‐temperature ionic liquids (RTILs) can be prepared by combining a luminescent anion (more common) or cation with appropriate counter ions, rendering new luminescent soft materials. These RTILs are still new, and many of their photochemical properties are not well known. A novel intrinsic luminescent RTIL based on the 8‐anilinonaphthalene‐1‐sulfonate ([ANS]) anion combined with the trihexyltetradecylphosphonium ([P6,6,6,14]) cation was prepared and characterized by spectroscopic techniques. Detailed photophysical studies highlight the influence of the ionic liquid environment on the ANS fluorescence, which together with rheological and 1H NMR experiments illustrate the effects of both the viscosity and electrostatic interactions between the ions. This material is liquid at room temperature and possesses a glass transition temperature (Tg) of 230.4 K. The fluorescence is not highly sensitive to factors such as temperature, but owing to its high viscosity, dynamic Stokes shift measurements reveal very slow components for the IL relaxation. 相似文献
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Dr. Lei He Prof. Wen-Cui Li Shuang Xu Prof. An-Hui Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(13):3209-3218
Microporous carbons afford high surface areas, large pore volumes, and good conductivity, and are fascinating over a wide range of applications. Traditionally synthesized microporous carbon materials usually suffer from some limitations, such as poor accessibility and slow mass transport of molecules due to the micrometer-scale diffusion pathways and space confinement imposed by small pore sizes. Two-dimensional microporous carbon materials, denoted as microporous carbon nanosheets (MCNs), possess nanoscale thickness, which allows fast mass and heat transport along the z axis; thus overcoming the drawbacks of their bulk counterparts. Herein, recent breakthroughs in the synthetic strategies for MCNs are summarized. Three typical methods are discussed in detail with several examples: pyrolysis of organic precursors with 2D units, a templating method that uses wet chemistry, and the molten salt method. Among them, molecular-based assembly of MCNs in the liquid phase shows more controllable morphology, thickness, and pore size distribution. Finally, challenges in this research area are discussed to inspire future explorations. 相似文献