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31.
Shanshan Sun Litao Wang Jiasheng Wang Wenjing Lv Qinghua Yu Dong Pei Siqi Han Xingyu Li Miao Wang Sheng Liu Xiangao Quan Mei Lv 《Journal of separation science》2023,46(16):2200935
In this work, homochiral reduced imine cage was covalently bonded to the surface of the silica to prepare a novel high-performance liquid chromatography stationary phase, which was applied for the multiple separation modes such as normal phase, reversed-phase, ion exchange, and hydrophilic interaction chromatography. The successful preparation of the homochiral reduced imine cage bonded silica stationary phase was confirmed by performing a series of methods including X-ray photoelectron spectroscopy, thermogravimetric analysis, and infrared spectroscopy. From the extracted results of the chiral resolution in normal phase and reversed-phase modes, it was demonstrated that seven chiral compounds were successfully separated, among which the resolution of 1-phenylethanol reached the value of 3.97. Moreover, the multifunctional chromatographic performance of the new molecular cage stationary phase was systematically investigated in the modes of reversed-phase, ion exchange, and hydrophilic interaction chromatography for the separation and analysis of a total of 59 compounds in eight classes. This work demonstrated that the homochiral reduced imine cage not only achieved multiseparation modes and multiseparation functions performance with high stability, but also expanded the application of the organic molecular cage in the field of liquid chromatography. 相似文献
32.
采用水热法制备了一种新型稀土配位聚合物[Dy(3-PA)3(H2O)]n(3-PA=3-吡啶丙烯酸)(1),并通过X射线单晶衍射结构分析、元素分析、红外光谱、热重分析对配合物1进行了结构表征.结构分析表明,标题配合物属于三斜晶系,Pī空间群,晶胞参数为:a=0.617 16(5)nm,b=1.270 45(11)nm,c=1.564 03(13)nm,α=111.557 0(10)°,β=90.307 0(10)°,γ=95.342 0(10)°,V=1.134 54(16)nm3,Z=2.金属离子Dy(III)通过配体3-AP羧基的桥联作用,链接成为一维双螺旋链状配位聚合物. 相似文献
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Catalyst‐Controlled Stereoselective Olefin Metathesis as a Principal Strategy in Multistep Synthesis Design: A Concise Route to (+)‐Neopeltolide 下载免费PDF全文
Miao Yu Prof. Richard R. Schrock Prof. Amir H. Hoveyda 《Angewandte Chemie (International ed. in English)》2015,54(1):215-220
Molybdenum‐, tungsten‐, and ruthenium‐based complexes that control the stereochemical outcome of olefin metathesis reactions have been recently introduced. However, the complementary nature of these systems through their combined use in multistep complex molecule synthesis has not been illustrated. A concise diastereo‐ and enantioselective route that furnishes the anti‐proliferative natural product neopeltolide is now disclosed. Catalytic transformations are employed to address every stereochemical issue. Among the featured processes are an enantioselective ring‐opening/cross‐metathesis promoted by a Mo monoaryloxide pyrrolide (MAP) complex and a macrocyclic ring‐closing metathesis that affords a trisubstituted alkene and is catalyzed by a Mo bis(aryloxide) species. Furthermore, Z‐selective cross‐metathesis reactions, facilitated by Mo and Ru complexes, have been employed in the stereoselective synthesis of the acyclic dienyl moiety of the target molecule. 相似文献
35.
Dr. Wei‐Wei Xiong Jianwei Miao Dr. Kaiqi Ye Prof. Dr. Yue Wang Prof. Dr. Bin Liu Prof. Dr. Qichun Zhang 《Angewandte Chemie (International ed. in English)》2015,54(2):546-550
Inserting polymers into a crystalline inorganic matrix to understand the structure, position, and the structure–property relationships of the resulting composites is important for designing new inorganic‐organic materials and tuning their properties. Single crystals of polymer‐chalcogenide composites were successfully prepared by trapping polyethyleneglycol within a selenidostannate matrix under surfactant‐thermal conditions. This work might provide a new strategy for preparing novel crystalline polymer‐inorganic composites through encapsulating polymer chains within inorganic matrices. 相似文献
36.
Xi Dai Tao Zhang Zhi-Fang Du Xiang-Jian Cao Ming-Yu Chen Sheng-Wen Hu Jun-Ying Miao Bao-Xiang Zhao 《Analytica chimica acta》2015
We have developed the first two-photon colorimetric and ratiometric fluorescent probe, BICO, for the detection of bisulfite (HSO3−) in aqueous solution. The probe contains coumarin and benzimidazole moieties and can detect HSO3− based on the Michael addition reaction with a limit of detection 5.3 × 10−8 M in phosphate-buffered saline solution. The probe was used to detect bisulfite in tap water, sugar and dry white wine. Moreover, test strips were made and used easily. We successfully applied the probe to image living cells, using one-photon fluorescence imaging. BICO overcomes the limitations in sensitivity of previously reported probes and the solvation effect of bisulfite, which demonstrates its excellent value in practical application. 相似文献
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Syntheses,Structures, and Magnetic Properties of Two Cobalt(II) Metal‐Organic Frameworks Based on Y‐shaped 3,5,4′‐Azobenzenetricarboxylic Acid and Different N‐donor Ligands 下载免费PDF全文
Yu‐Ting Yang Chang‐Zheng Tu Jiao‐Jiao Miao Jun‐Li Li Guang Chen Hong‐Ju Yin Fei‐Xiang Cheng 《无机化学与普通化学杂志》2015,641(15):2576-2580
Two metal‐organic frameworks, [Co2(ABTC)(bimh)(OH)] · 2H2O ( 1 ) and [Co3(ABTC)2(dimb)4]n ( 2 ) [H3ABTC = 3,4′,5‐azobenzenetricarboxylic acid, bimh = 1,1′‐(1,4‐hexanediy)bis(imidazole), dimb = 1,4‐bis(1H‐imidazol‐1‐yl)benzene], were prepared under solvothermal conditions and structurally characterized. Complex 1 demonstrates a complicated 3D (3,8)‐connected tfz‐d net with (43)2(46.617.85) topology. The framework of 2 can be classified as a rare 3D (3,6,6)‐connected net with the Schäfli symbol of (4.62)2(42.610.83)(44.610.8), and exhibits an intriguing self‐penetrating motif. Meanwhile, the thermal stabilities and magnetic properties for 1 and 2 were also probed. 相似文献
39.
Nuo Duan Shijia Wu Shaoliang Dai Tingting Miao Jie Chen Zhouping Wang 《Mikrochimica acta》2015,182(5-6):917-923
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