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981.
Hui‐Min Lin Jian‐Rong Li Chao Mu Ao Li Xu‐Feng Liu Pei‐Hua Zhao Yu‐Long Li Zhong‐Qing Jiang Hong‐Ke Wu 《应用有机金属化学》2019,33(11)
Five monophosphine‐substituted diiron propane‐1,2‐dithiolate complexes as the active site models of [FeFe]‐hydrogenases have been synthesized and characterized. Reactions of complex [Fe2(CO)6{μ‐SCH2CH(CH3)S}] ( 1 ) with a monophosphine ligand tris(4‐methylphenyl)phosphine, diphenyl‐2‐pyridylphosphine, tris(4‐chlorophenyl)phosphine, triphenylphosphine, or tris(4‐fluorophenyl)phosphine in the presence of the oxidative agent Me3NO·2H2O gave the monophosphine‐substituted diiron complexes [Fe2(CO)5(L){μ‐SCH2CH(CH3)S}] [L = P(4‐C6H4CH3)3, 2 ; Ph2P(2‐C5H4N), 3 ; P(4‐C6H4Cl)3, 4 ; PPh3, 5 ; P(4‐C6H4F)3, 6 ] in 81%–94% yields. Complexes 2 – 6 have been characterized by elemental analysis, spectroscopy, and X‐ray crystallography. In addition, electrochemical studies revealed that these complexes can catalyze the reduction of protons to H2 in the presence of HOAc. 相似文献
982.
Three multinuclear Cu (II), Zn (II) and Cd (II) complexes, [Cu2(L)(μ‐OAc)]·CHCl2 ( 1 ), [Zn2(L)(μ‐OAc)(H2O)]·3CHCl3 ( 2 ) and [{Cd2(L)(OAc)(CH3CH2OH)}2]·2CH3CH2OH ( 3 ) with a single‐armed salamo‐like dioxime ligand H3L have been synthesized, and characterized by FT‐IR, UV–vis, X‐ray crystallography and Hirshfeld surfaces analyses. The ligand H3L has a linear structure and C‐H···π interactions between the two molecules. The complex 1 is a dinuclear Cu (II) complex, Cu1 and Cu2 are all five‐coordinate possessing distorted square pyramidal geometries. The complex 2 also forms a dinuclear Zn (II) structure, and Zn1 and Zn2 are all five‐coordinate bearing distorted trigonal bipyramidal geometries. The complex 3 is a symmetrical tetranuclear Cd (II) complex, and Cd1 is a hexa‐coordinate having octahedral configuration and Cd2 is hepta‐coordinate with a pentagonal bipyramidal geometry, and it has π···π interactions inside the molecule. In addition, fluorescence properties of the ligand and its complexes 1 – 3 have also been discussed. 相似文献
983.
984.
Bing Bai Meng Xu Nan Li Wenxing Chen Jiajia Liu Jia Liu Hongpan Rong Dieter Fenske Jiatao Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):4906-4911
Thiol‐ and solvent‐coordinated cation exchange kinetics have been applied to engineer the composition and crystallinity of novel nanocrystals. The detailed thermodynamics and kinetics of the reactions were explored by NMR spectroscopy, time‐dependent photoluminescence (PL) characterizations and theoretical simulations. The fine structure of the colloidal semiconductor nanocrystals (CSNCs) was investigated by X‐ray absorption near‐edge structure (XANES) and extended X‐ray absorption fine structure (EXAFS). In this way, high‐quality p‐type Ag‐doped ZnS quantum dots (QDs) and Au@ZnS hetero‐nanocrystals with a cubic phase ZnS shell were synthesized successfully.The unprecedented dominant Ag+‐dopant‐induced fluorescence and p‐type conductivity in the zinc‐blende ZnS are reported. 相似文献
985.
Qian Cheng Weiheng Xu Shiyi Qin Subhabrata Das Tianwei Jin Aijun Li Alex Ceng Li Boyu Qie Pengcheng Yao Haowei Zhai Changmin Shi Xin Yong Yuan Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(17):5613-5617
The lithium–sulfur battery is an attractive option for next‐generation energy storage owing to its much higher theoretical energy density than state‐of‐the‐art lithium‐ion batteries. However, the massive volume changes of the sulfur cathode and the uncontrollable deposition of Li2S2/Li2S significantly deteriorate cycling life and increase voltage polarization. To address these challenges, we develop an ?‐caprolactam/acetamide based eutectic‐solvent electrolyte, which can dissolve all lithium polysulfides and lithium sulfide (Li2S8–Li2S). With this new electrolyte, high specific capacity (1360 mAh g?1) and reasonable cycling stability are achieved. Moreover, in contrast to conventional ether electrolyte with a low flash point (ca. 2 °C), such low‐cost eutectic‐solvent‐based electrolyte is difficult to ignite, and thus can dramatically enhance battery safety. This research provides a new approach to improving lithium–sulfur batteries in aspects of both safety and performance. 相似文献
986.
Youqian Xu Jinbo Fei Guangle Li Tingting Yuan Xia Xu Junbai Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(17):5628-5632
Multiple‐enzyme‐involving cascade reactions that yield bioenergy are necessary in natural oxidative phosphorylation. However, in vitro applications are hampered by the sensitivity of catalytic activity to environmental adaptation. Herein, we explore nanozyme‐catalyzed cascade reactions in an assembled hybrid architecture for mitochondria‐mimicking oxidative phosphorylation. Hollow silica microspheres containing trapped gold nanoparticles were synthesized to promote two enzyme‐like catalytic reactions that transform glucose into gluconic acid in the presence of oxygen. The resulting transmembrane proton gradient drives natural ATP synthase reconstituted on the surface to convert ADP and inorganic phosphate into ATP. The assembled architecture possesses high activity for oxidative phosphorylation, comparable to that of natural mitochondria. This study provides a new natural–artificial hybrid prototype for exploring bioenergy supply systems and holds great promise for ATP‐powered bioapplications. 相似文献
987.
Snke Oswald Nathan A. Seifert Fabian Bohle Maxim Gawrilow Stefan Grimme Wolfgang Jger Yunjie Xu Martin A. Suhm 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):5134-5138
1,1,1,3,3,3‐hexafluoro‐propan‐2‐ol aggregates preferentially into an achiral dimer of achiral monomers, but the trimer is found to prefer three metastable chiral monomer units arranged into a strained OH???O hydrogen‐bonded ring, which is reinforced by secondary CH???FC interactions. This is shown by a combination of infrared, microwave, and Raman spectroscopy in supersonic jet expansions and supported by high‐level quantum chemical calculations. It involves an activation of the monomers by >15 kJ mol?1, clearly driven by the much stronger hydrogen‐bond interaction available to the gauche and even more to the cis monomer units. 相似文献
988.
Xu‐Jie Qin Tyler J. Rauwolf Pan‐Pan Li Hui Liu James McNeely Yan Hua Hai‐Yang Liu John A. Porco 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(13):4335-4340
Rhodomyrtusials A–C, the first examples of triketone‐sesquiterpene meroterpenoids featuring a unique 6/5/5/9/4 fused pentacyclic ring system were isolated from Rhodomyrtus tomentosa, along with several biogenetically‐related dihydropyran isomers. Two bis‐furans and one dihydropyran isomer showed acetylcholinesterase (AChE) inhibitory activity. Structures of the isolates were unambiguously established by a combination of spectroscopic data, ECD analysis, and total synthesis. Bioinspired total syntheses of six isolates were achieved in six steps utilizing a reactive enetrione intermediate generated in situ from a readily available hydroxy‐endoperoxide precursor. 相似文献
989.
Xing Wei Meng‐Jiao Zhu Zhe Cheng Mengjeu Lee Hong Yan Changsheng Lu Jing‐Juan Xu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(10):3194-3198
The aggregation‐induced electrochemiluminescence (AIECL) of carboranyl carbazoles in aqueous media was investigated for the first time. Quantum yields, morphologies, and particle sizes were observed to determine the electrochemiluminescence (ECL) performance of these aggregated organic dots (ODs). All compounds exhibit much higher ECL stability and intensity than the carborane‐free compound, demonstrating the essential role of the carboranyl motif. Moreover, the results of cyclic voltammetry (CV) suggest that oxidation/reduction reactions take place at the carboranyl motif. The excited states of ODs were proposed to be generated by the mechanism of surface state transitions. More importantly, these compounds show a reductive–oxidative mechanism in contrast to other organic materials that show oxidative–reductive mechanisms. Our experiments and data have established the relation between AIE organic structures and ECL properties that has a strong potential for biological and diagnostic applications. 相似文献
990.
Kyuho Moon Fei Xu Mohammad R. Seyedsayamdost 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(18):6034-6038
The majority of natural product biosynthetic gene clusters in bacteria are silent under standard laboratory growth conditions, making it challenging to uncover any antibiotics that they may encode. Herein, bioactivity assays are combined with high‐throughput elicitor screening (HiTES) to access cryptic, bioactive metabolites. Application of this strategy in Saccharopolyspora cebuensis, with inhibition of Escherichia coli growth as a read‐out, led to the identification of a novel lanthipeptide, cebulantin. Extensive NMR spectroscopic analysis allowed the elucidation of the structure of cebulantin. Subsequent bioactivity assays revealed it to be an antibiotic selective for Gram‐negative bacteria, especially against Vibrio species. This approach, referred to as bioactivity‐HiTES, has the potential to uncover cryptic metabolites with desired biological activities that are hidden in microbial genomes. 相似文献