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101.
Yanfei Yang Xiaodan Cao Kazimierz Surowiec Richard A. Bartsch 《Journal of inclusion phenomena and macrocyclic chemistry》2014,78(1-4):387-395
Four cone p-tert-butylcalix[4]arene-1,3-monothiacrown-5 ligands each with two N-(X)sulfonyl carbamoylmethoxy side arms are synthesized for comparison with analogs having only oxygen heteroatoms in the crown ether ring. Solvent extractions of hard alkali metal and alkaline earth metal cations, intermediate Pb2+, and soft Hg2+ from aqueous solutions into chloroform by these ligands are utilized to probe the effects of sulfur replacement in the crown ether ring on metal ion complexation. 相似文献
102.
Huan Luo Yanfei Liu Dong Liang Zhiyou Hao Yan Wang Chunlei Zhang Qingjian Zhang Dequan Yu 《Helvetica chimica acta》2013,96(10):1936-1942
The first asymmetric total synthesis of (?)‐ligustiphenol is reported. The key step was conducted by exploiting a steric hindrance effect to control the formation of the adduct in a nucleophilic α‐Li‐phenolate addition reaction to the intermediate α‐oxo (?)‐menthyl ester. The synthesis is concise and feasible for the construction of analogous compounds and investigation of their biological activity. 相似文献
103.
Yanfei Wang Benjamin W. Roose John P. Philbin Jordan L. Doman Prof. Ivan J. Dmochowski 《Angewandte Chemie (International ed. in English)》2016,55(5):1733-1736
A supramolecular strategy for detecting specific proteins in complex media by using hyperpolarized 129Xe NMR is reported. A cucurbit[6]uril (CB[6])‐based molecular relay was programmed for three sequential equilibrium conditions by designing a two‐faced guest (TFG) that initially binds CB[6] and blocks the CB[6]–Xe interaction. The protein analyte recruits the TFG and frees CB[6] for Xe binding. TFGs containing CB[6]‐ and carbonic anhydrase II (CAII)‐binding domains were synthesized in one or two steps. X‐ray crystallography confirmed TFG binding to Zn2+ in the deep CAII active‐site cleft, which precludes simultaneous CB[6] binding. The molecular relay was reprogrammed to detect avidin by using a different TFG. Finally, Xe binding by CB[6] was detected in buffer and in E. coli cultures expressing CAII through ultrasensitive 129Xe NMR spectroscopy. 相似文献
104.
Nakanishi T Shen Y Wang J Yagai S Funahashi M Kato T Fernandes P Möhwald H Kurth DG 《Journal of the American Chemical Society》2008,130(29):9236-9237
Fullerenes, C60, modified with long alkyl chains form long-range ordered lamellar mesophases permitting a high C60 content. The mesomorphic fullerenes feature reversible electrochemistry and a comparably high electron carrier mobility making them attractive components for fullerene-based soft materials. 相似文献
105.
Under the same experimental condition, changing the kinds of the transition metal (TM) of the reaction, we gained two new
compounds: Na3[Cu(Gly)2][Cr(OH)6Mo6O18]·13H2O 1, and NaCo2(gly)6ClO4
2. Compound 1 exhibits an unusual three-dimensional (3D) network constructed from [Cr(OH)6Mo6O18]3− building blocks, trinuclear Na+ ions and [Cu(gly)2] coordination complexes as linkers, representing the first example of a 3D extended framework based on Anderson type polyanions
and amino acid molecules. Compound 2 consists of an unusual 3D network grafted with Na[Co(gly)3]6 complexes. Moreover, compound 2 contains left-handed and right-handed helical chains.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
106.
107.
Xiaoxuan Wang Shuyuan Li Zhi Yuan Yanfei Sun Zheng Tang Xueying Gao Huiying Zhang Jingxian Li Shiyu Wang Dongchun Yang Jiangzhou Xie Zhiyu Yang Yi-Ming Yan 《Angewandte Chemie (International ed. in English)》2023,62(29):e202303794
Electrocatalytic nitrogen reduction reaction (ENRR) has emerged as a promising approach to synthesizing green ammonia under ambient conditions. Tungsten (W) is one of the most effective ENRR catalysts. In this reaction, the protonation of intermediates is the rate-determining step (RDS). Enhancing the adsorption of intermediates is crucial to increase the protonation of intermediates, which can lead to improved catalytic performance. Herein, we constructed a strong interfacial electric field in WS2-WO3 to elevate the d-band center of W, thereby strengthening the adsorption of intermediates. Experimental results demonstrated that this approach led to a significantly improved ENRR performance. Specifically, WS2-WO3 exhibited a high NH3 yield of 62.38 μg h−1 mgcat−1 and a promoted faraday efficiency (FE) of 24.24 %. Furthermore, in situ characterizations and theoretical calculations showed that the strong interfacial electric field in WS2-WO3 upshifted the d-band center of W towards the Fermi level, leading to enhanced adsorption of −NH2 and −NH intermediates on the catalyst surface. This resulted in a significantly promoted reaction rate of the RDS. Overall, our study offers new insights into the relationship between interfacial electric field and d-band center and provides a promising strategy to enhance the intermediates adsorption during the ENRR process. 相似文献
108.
Xiuping Yuan Yiliang Zhang Yanfei Li Jianjun Yin Simin Wang Prof. Tao Xiong Prof. Qian Zhang 《Angewandte Chemie (International ed. in English)》2023,62(48):e202313770
Herein, we report an unprecedented copper-catalyzed highly enantio- and diastereoselective radical oxyboration of β-substituted styrenes. The lynchpin of success is ascribed to the development of a late-stage stereomutation strategy, which enables enantioenriched cis-isomers among a couple of early-generated diastereomers to be converted into trans-isomer counterparts, thus fulfilling high diastereocontrol; while the degree of enantio-differentiation is determined by the borocupration process of the C=C bond. This reaction provides an efficient protocol to access enantioenriched trans-1,2- dioxygenation products. The value of this method has further been highlighted in a diversity of follow-up stereospecific transformations and further modifying complex molecules. 相似文献
109.
Kaiqing Wu Prof. Ran Chen Prof. Zhixin Zhou Xinghua Chen Yanqin Lv Jin Ma Prof. Yanfei Shen Prof. Songqin Liu Prof. Yuanjian Zhang 《Angewandte Chemie (International ed. in English)》2023,62(12):e202217078
Facile evaluation of oxygen reduction reaction (ORR) kinetics for electrocatalysts is critical for sustainable fuel-cell development and industrial H2O2 production. Despite great success in ORR studies using mainstream strategies, such as the membrane electrode assembly, rotation electrodes, and advanced surface-sensitive spectroscopy, the time and spatial distribution of reactive oxygen species (ROS) intermediates in the diffusion layer remain unknown. Using time-dependent electrochemiluminescence (Td-ECL), we report an intermediate-oriented method for ORR kinetics analysis. Owing to multiple ultrasensitive stoichiometric reactions between ROS and the ECL emitter, except for electron transfer numbers and rate constants, the potential-dependent time and spatial distribution of ROS were successfully obtained for the first time. Such exclusively uncovered information would guide the development of electrocatalysts for fuel cells and H2O2 production with maximized activity and durability. 相似文献
110.
Yanfei Zhu Lidan Guo Jun Guo Luyang Zhao Chunyan Li Xueying Qiu Yang Qin Xianrong Gu Prof. Xiangnan Sun Prof. Zhiyong Tang 《Angewandte Chemie (International ed. in English)》2023,62(4):e202213208
As a new type of inorganic-organic hybrid semiconductor, quantum-confined atomically precise metal nanoclusters (MNCs) have been widely applied in the fields of chemical sensing, optical imaging, biomedicine and catalysis. Herein, we successfully design and fabricate the first example of MNC-based spin valves (SVs) that exhibit remarkable magnetoresistance (MR) value up to 1.6 % even at room temperature (300 K). The concomitant photoresponse of MNC-based SVs unambiguously confirms that the spin-polarized electron transmission takes place across the MNC interlayer. Furthermore, the spin-dependent transport property of MNC-based SVs is largely varied by changing the atomic structure of MNCs. Both experimental proofs and quantum chemistry calculations reveal that the atomic structure-discriminative spin transport behavior is attributed to the distinct spin-orbit coupling (SOC) effect of MNCs. 相似文献