Angewandte Chemie International Edition
Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
The following papers are very important in the opinion of two referees.
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On the Role of the Electronic Structure of the Heteronuclear Oxide Cluster [Ga2Mg2O5].+ in the Thermal Activation of Methane and Ethane: An Unusual Doping Effect
Dr. Jilai Li, Dr. Xiao-Nan Wu, Dr. Maria Schlangen, Dr. Shaodong Zhou, Dr. Patricio González-Navarrete, Dr. Shiya Tang and Prof. Dr. Helmut Schwarz
Bridging oxygen: A combination of mass spectrometry and quantum chemical calculations shows that [Ga2Mg2O5].+, bearing an unpaired electron at a bridging oxygen atom, is capable of activating the CH bond of methane. The roles of spin density and charge distributions in hydrogen-atom transfer processes provide important guidance for the rational design of catalysts.
Oxidative Addition of Carbon–Carbon Bonds to Gold
Dr. Maximilian Joost, Dr. Laura Estévez, Dr. Karinne Miqueu, Dr. Abderrahmane Amgoune and Dr. Didier Bourissou
Gold(I) complexes ([(DPCb)Au]+) readily insert into the four-membered rings of biphenylene and benzocyclobutenone. These transformations afforded well-defined cationic organogold(III) complexes that were isolated and fully characterized. [(DPCb)Au]+ is the only complex to cleave selectively either the C(aryl)C(O) or the C(alkyl)C(O) bond of benzocyclobutenone under kinetic/thermodynamic control. DPCb=diphosphinocarborane.
Interrupted Chalcogenide-Based Zeolite-Analog Semiconductor: Atomically Precise Doping for Tunable Electro-/Photoelectrochemical Properties
Jian Lin, Youzhen Dong, Qian Zhang, Dandan Hu, Prof. Dr. Na Li, Dr. Le Wang, Prof. Dr. Yang Liu and Prof. Dr. Tao Wu
Zeolitic architecture: An interrupted chalcogenide-based zeolite-analog semiconductor with an entirely new boracite-related framework and specific sites at the interrupted section is reported. The specific indium sites serving as effective electrocatalytic active centers for the oxygen reduction reaction proved to be atomically precisely doped by trivalent bismuth ions.
Well-Defined CuC2F5 Complexes and Pentafluoroethylation of Acid Chlorides
Liubov I. Panferova, Fedor M. Miloserdov, Dr. Anton Lishchynskyi, Dr. Marta Martínez Belmonte, Dr. Jordi Benet-Buchholz and Prof. Vladimir V. Grushin
Four well-defined CuC2F5 complexes have been prepared and fully characterized, with [(phen)Cu(PPh3)C2F5] (phen=1,10-phenanthroline) proving to be a remarkably efficient fluoroalkylating agent for a broad variety of acid chlorides (see scheme). The developed procedure represents the first general method for the one-step conversion of RCOCl into valuable pentafluoroethyl ketones.
Synthesis of Carbon/Sulfur Nanolaminates by Electrochemical Extraction of Titanium from Ti2SC
Dr. Meng-Qiang Zhao, Morgane Sedran, Zheng Ling, Maria R. Lukatskaya, Olha Mashtalir, Michael Ghidiu, Boris Dyatkin, Darin J. Tallman, Prof. Thierry Djenizian, Prof. Michel W. Barsoum and Prof. Yury Gogotsi
Carbon/sulfur nanolaminates composed of multi-layered C/S flakes with predominantly amorphous, and some graphene-like, structures were synthesized by electrochemical extraction of Ti from a Ti2SC MAX phase. This approach provides a novel method for the room-temperature synthesis of “AX” layered structures by the selective extraction of “M” from the MAX phases.
Organoaluminum-Mediated Direct Cross-Coupling Reactions
Hiroki Minami, Dr. Tatsuo Saito, Dr. Chao Wang and Prof. Dr. Masanobu Uchiyama
All in Al: Simply heating an arylaluminum (ArAlMe2⋅LiCl) and an organic halide RX (R=aryl, alkenyl, alkynyl; X=I, Br, Cl) without any external catalyst results in a smooth and direct cross-coupling reaction taking place. This approach enables the efficient, chemo-/stereoselective formation of coupling products with broad functional group compatibility.
Structural Characterization of a Hydroperoxo Nickel Complex and Its Autoxidation: Mechanism of Interconversion between Peroxo, Superoxo, and Hydroperoxo Species
Christoph A. Rettenmeier, Prof. Hubert Wadepohl and Lutz H. Gade
Pincer-stabilized nickel(I) complexes readily react with molecular oxygen to form dinuclear 1,2-μ-peroxo-bridged nickel(II) complexes, which are the major components of a dynamic equilibrium with the corresponding mononuclear superoxo species. The peroxo complexes further react with hydrogen peroxide to give the corresponding nickel(II) hydroperoxides.
A Covalent Approach for Site-Specific RNA Labeling in Mammalian Cells
Fahui Li, Jianshu Dong, Xiaosong Hu, Weimin Gong, Jiasong Li, Jing Shen, Huifang Tian and Jiangyun Wang
Tag and click: The ability to specifically label RNAs in vitro and in mammalian cells would be highly significant for RNA research, however, covalent RNA labeling methods with scope and versatility comparable to those for protein labeling have not been reported. A method was developed for the site- and sequence-specific covalent labeling of RNAs in mammalian cells, based on the action of tRNAIle2-agmatidine synthetase (Tias) and click chemistry.
Free-Standing Gold-Nanoparticle Monolayer Film Fabricated by Protein Self-Assembly of α-Synuclein
Junghee Lee, Dr. Ghibom Bhak, Dr. Ji-Hye Lee, Woohyun Park, Minwoo Lee, Dr. Daekyun Lee, Prof. Noo Li Jeon, Prof. Dae H. Jeong, Prof. Kookheon Char and Prof. Seung R. Paik
Film producer: Protein-based free-standing gold-nanoparticle monolayer films are fabricated by self-assembly between α-synuclein proteins coating the nanoparticles. The film can be scaled-up to 4-inch-wafer size. The high flexibility of the film in solvent allows it to wrap round curved surfaces on the micrometer-scale. Additionally, the monolayer film is readily patterned into free-floating multi-hole sheets and an unprecedented film containing two different sized nanoparticles is also fabricated (see photo).
Dipolar Rotors Orderly Aligned in Mesoporous Fluorinated Organosilica Architectures
Dr. Silvia Bracco, Dr. Mario Beretta, Dr. Alice Cattaneo, Prof. Angiolina Comotti, Prof. Andrea Falqui, Dr. Ke Zhao, Prof. Charles Rogers and Prof. Piero Sozzani
Oriented molecular rotors: Fluorinated molecular rotors (see picture) were engineered in mesoporous hybrid organosilica architectures with crystalline order in their walls. The rotor dynamics was established by magic angle spinning NMR and dielectric measurements, indicating a rotational correlation time as short as 10−9 s at 325 K. The dynamics was modulated by I2 vapors entering the pores.
Flow-Enabled Self-Assembly of Large-Scale Aligned Nanowires
Bo Li, Chuchu Zhang, Beibei Jiang, Dr. Wei Han and Prof. Zhiqun Lin
Metallic nanowires are obtained by using highly oriented DNA nanowires as templates. A swelling-induced transfer printing technique is employed to transfer the ultralong DNA nanowires onto a desirable substrate; metallic nanowires are then generated by exposing the DNA nanowires preloaded with metal salts to an oxygen plasma.
Caterpillar Track Complexes in Template-Directed Synthesis and Correlated Molecular Motion
Shiqi Liu, Dr. Dmitry V. Kondratuk, Dr. Sophie A. L. Rousseaux, Dr. Guzmán Gil-Ramírez, Dr. Melanie C. O'Sullivan, Jonathan Cremers, Prof. Tim D. W. Claridge and Prof. Harry L. Anderson
Turning in unison: Two wheel-like templates work together to direct the synthesis of a nanoring. Their rotation is synchronized in the resulting 2:1 caterpillar track complex.
Impact of Hydrogenolysis on the Selectivity of the Fischer–Tropsch Synthesis: Diesel Fuel Production over Mesoporous Zeolite Y-Supported Cobalt Nanoparticles
Xiaobo Peng, Dr. Kang Cheng, Dr. Jincan Kang, Bang Gu, Xiang Yu, Prof. Dr. Qinghong Zhang and Prof. Dr. Ye Wang
Gas up! A mesoporous zeolite Y-supported cobalt catalyst, which is highly selective for the direct conversion of syngas into diesel fuel, has been developed by effective control of hydrogenolysis. The sizes of the cobalt particles and support mesopores are key factors in determining the activity and selectivity of hydrogenolysis.
Live-Cell MRI with Xenon Hyper-CEST Biosensors Targeted to Metabolically Labeled Cell-Surface Glycans
Dr. Christopher Witte, Dr. Vera Martos, Dr. Honor May Rose, Dr. Stefan Reinke, Stefan Klippel, Dr. Leif Schröder and Prof. Dr. Christian P. R. Hackenberger
Xenon’s sweet spot: A multimodal bioorthogonal xenon MRI biosensor was used to image the distribution of metabolically labeled cell-surface glycans with nanomolar sensitivity. This work expands the application of MRI to the imaging of glycome targets that have been difficult to investigate with conventional MRI contrast agents.
Strong Lithium Polysulfide Chemisorption on Electroactive Sites of Nitrogen-Doped Carbon Composites For High-Performance Lithium–Sulfur Battery Cathodes
Dr. Jiangxuan Song, Mikhail L. Gordin, Dr. Terrence Xu, Shuru Chen, Zhaoxin Yu, Dr. Hiesang Sohn, Dr. Jun Lu, Dr. Yang Ren, Dr. Yuhua Duan and Prof. Donghai Wang
A composite that consists of carbon-nanotube-interpenetrated mesoporous nitrogen-doped carbon spheres (MNCS/CNT) can strongly chemisorb polysulfides and was used as a cathode material for lithium–sulfur batteries. Moreover, the highly conductive nitrogen-doped carbon material enables direct and easy redox reactions of the adsorbed polysulfides, which leads to good electrode kinetics.
The Fluorenyl Cation
Paolo Costa, Iris Trosien, Miguel Fernandez-Oliva, Dr. Elsa Sanchez-Garcia and Prof. Dr. Wolfram Sander
Frozen: In spite of its antiaromatic destabilization, the elusive fluorenyl cation could be isolated in amorphous water ice at temperatures below 30 K by photolysis of diazofluorene. Its experimentally determined IR bands were found to nicely match predictions from QM/MM calculations.
Catalytic Asymmetric Hydroalkenylation of Vinylarenes: Electronic Effects of Substrates and Chiral N-Heterocyclic Carbene Ligands
Prof. Dr. Chun-Yu Ho, Chun-Wa Chan and Lisi He
Crossed: An asymmetric tail-to-tail cross-hydroalkenylation of vinylarenes with terminal olefins was catalyzed by NiH complexes with chiral N-heterocyclic carbenes (NHCs). Depending on steric and electronic effects of the substrates and NHC ligands, the reaction can provide branched gem-disubstituted olefins with high enantio- (up to 94 % ee) and chemoselectivity (cross/homo product ratio: up to 99:1).
Ligand-Promoted Oxidative Cross-Coupling of Aryl Boronic Acids and Aryl Silanes by Palladium Catalysis
Jingxun Yu, Jun Liu, Guangfa Shi, Changdong Shao and Prof. Dr. Yanghui Zhang
Two nucleophiles: The first cross-coupling reaction between aryl silanes and aryl boronic acids is one of the very few examples of coupling reactions between two nucleophilic organometallic reagents and provides access to biaryl compounds. With the commercially available ligand BINAP, the formation of the homocoupling products was suppressed, and the reaction yielded the cross-coupling products with high selectivity.
A Carbon–Air Battery for High Power Generation
Binbin Yang, Prof. Ran Ran, Yijun Zhong, Dr. Chao Su, Prof. Moses O. Tadé and Prof. Zongping Shao
Midair refueling: A carbon–air battery based on a anode-supported tubular solid-oxide fuel cell integrated with a CO2 separation membrane (see picture) composed of a CO32− mixture and an O2− conducting phase showed both high energy density and power output. A small stack composed of two batteries can be operated continuously for 200 min, which is promising for use as a portable power device.
Remarkably Enhanced Gas Separation by Partial Self-Conversion of a Laminated Membrane to Metal–Organic Frameworks
Dr. Yi Liu, Dr. Jia Hong Pan, Nanyi Wang, Frank Steinbach, Dr. Xinlei Liu and Prof. Jürgen Caro
From LDH to MOF: The partial transformation of a ZnAl-NO3 layered double hydroxide (LDH) membrane to a ZIF-8 metal–organic framework (MOF) top layer led to the formation of the composite membrane ZIF-8-ZnAl-NO3 LDH. This membrane is characterized by remarkably enhanced H2/CH4 gas separation and H2 permeance.
Lithium Imide Synergy with 3d Transition-Metal Nitrides Leading to Unprecedented Catalytic Activities for Ammonia Decomposition
Jianping Guo, Peikun Wang, Prof. Dr. Guotao Wu, Prof. Dr. Anan Wu, Daqiang Hu, Prof. Dr. Zhitao Xiong, Prof. Dr. Junhu Wang, Pei Yu, Fei Chang, Zheng Chen and Prof. Dr. Ping Chen
Beyond an electronic promoter: A synergy between Li2NH and 3d transition-metal nitrides leads to unprecedented catalytic activities for NH3 decomposition. Li2NH acts as more than just an electronic promoter: it is an NH3 transmitting agent and favors the formation of a higher N-content intermediate, thereby altering the overall reaction energetics.
A D-Peptide Ligand of Nicotine Acetylcholine Receptors for Brain-Targeted Drug Delivery
Xiaoli Wei, Dr. Changyou Zhan, Qing Shen, Prof. Wei Fu, Cao Xie, Jie Gao, Chunmei Peng, Prof. Ping Zheng and Prof. Weiyue Lu
A D-peptide ligand of nicotine acetylcholine receptors (nAChRs), termed DCDX, was developed. The function of DCDX as a D-peptide antagonist of nAChRs was experimentally and computationally validated. DCDX exhibits exceptional stability during nAChRs-mediated transcytosis and in blood circulation, offering potential for brain-targeting drug delivery in the treatment of central nervous system diseases.
Synergistic Interplay of a Non-Heme Iron Catalyst and Amino Acid Coligands in H2O2 Activation for Asymmetric Epoxidation of α-Alkyl-Substituted Styrenes
Olaf Cussó, Dr. Xavi Ribas, Dr. Julio Lloret-Fillol and Dr. Miquel Costas
Come on styrene: Using amino acids as coligands for bioinspired non-heme iron catalysts, the substrate scope of epoxidation reactions with aqueous H2O2 is extended to the challenging α-styrenes. Thus, these systems can be adapted for new substrates classes simple by changing the amino acid coligand.
Electron Tunneling Rates in Respiratory Complex I Are Tuned for Efficient Energy Conversion
Prof. Dr. Simon de Vries, Dr. Katerina Dörner, Marc J. F. Strampraad and Prof. Dr. Thorsten Friedrich
The reduction of ubiquinone by NADH is catalyzed by flavin mononucleotide and a chain of seven iron–sulfur centers. The electron transfer rates between the centers indicate that the Fe–S chain synchronizes the electron transfer rate to match the time scale of the conformational changes required for proton translocation.