Angewandte Chemie International Edition
© WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
The following papers are very important in the opinion of two referees.
You are invited to comment on published VIPs. Please use the link given at the end of each such abstract. Scientific comments may be forwarded to the authors by the editorial office and may be posted on this page. Kindly let us know if your comments are for the editorial office only, the author, or the public as well.
Formation of Ruthenium Carbenes by gem-Hydrogen Transfer to Internal Alkynes: Implications for Alkyne trans-Hydrogenation
M. Sc. Markus Leutzsch, Dr. Larry M. Wolf, Puneet Gupta, Dr. Michael Fuchs, Prof. Walter Thiel, Dr. Christophe Farès and Prof. Alois Fürstner
Let′s stay together: Certain ruthenium complexes are able to catalyze the stereochemically highly unusual trans-hydrogenation of internal alkynes, but can also effect a geminal hydrogenation, during which both H atoms of a single H2 precursor are delivered to the very same alkyne C atom whilst the neighboring C atom is converted into a metal carbene. The significance of this finding is analyzed by PHIP NMR spectroscopy (PHIP=para-hydrogen-induced polarization transfer) and density functional calculations.
Conductive Elastomers with Autonomic Self-Healing Properties
Kun Guo, Da-Li Zhang, Xiao-Mei Zhang, Prof. Dr. Jian Zhang, Prof. Dr. Li-Sheng Ding, Prof. Dr. Bang-Jing Li and Prof. Dr. Sheng Zhang
Candidates for smart robotics: Self-healing conductive composites were prepared by connecting single-walled carbon nanotubes (SWCNTs) to a polymer network through host–guest interactions (see picture). The poly(2-hydroxyethyl methacrylate)–SWCNT composite combines bulk electrical conductivity, proximity sensitivity, humidity sensitivity, and autonomic self-healing properties.
Orthogonal Light-Induced Self-Assembly of Nanoparticles using Differently Substituted Azobenzenes
Dr. Debasish Manna, Dr. Thumu Udayabhaskararao, Dr. Hui Zhao and Dr. Rafal Klajn
Precise control of the assembly of selected components within complex mixtures is a challenging task. In their Communication (DOI: 10.1002/anie.201502419), R. Klajn et al. approach this challenge by decorating the surfaces of differently sized nanoparticles with two distinct azobenzenes that isomerize upon exposure to different wavelengths of light. The cover illustrates how ultraviolet and blue light can be used to selectively assemble large and small nanoparticles, respectively (Cover image: Ella Marushchenko).
Observation of a Thermally Accessible Triplet State Resulting from Rotation around a Main-Group π Bond
Arseni Kostenko, Dr. Boris Tumanskii, Dr. Miriam Karni, Prof. Shigeyoshi Inoue, Prof. Masaaki Ichinohe, Prof. Akira Sekiguchi and Prof. Yitzhak Apeloig
A triplet diradical that is formed in a thermally induced rotation around a main-group π bond, that is the SiSi double bond of 1, was directly observed by EPR spectroscopy. Both experiment and theory support a thermal equilibrium between singlet 1 and the perpendicular triplet diradical 2.
A High-Voltage and Ultralong-Life Sodium Full Cell for Stationary Energy Storage
Shaohua Guo, Dr. Pan Liu, Dr. Yang Sun, Kai Zhu, Dr. Jin Yi, Prof. Mingwei Chen, Prof. Masayoshi Ishida and Prof. Haoshen Zhou
In full flow: A sodium full cell has been designed based on Na0.66Ni0.17Co0.17Ti0.66O2 as both the cathode and anode. It exhibits the highest average voltage of approximately 3.10 V in the symmetric cells and the longest cycle life (75.9 % capacity retention after 1000 cycles) in all reported sodium full cells, and also shows a usable capacity and superior rate capability.
Unusual H-bond Topology and Bifurcated H-bonds in the 2-Fluoroethanol Trimer
Dr. Javix Thomas, Dr. Xunchen Liu, Prof. Dr. Wolfgang Jäger and Prof. Dr. Yunjie Xu
The unexpected: The trimer of 2-fluoroethanol demonstrates a striking case of chirality-induced H-bond topology switching. It strongly favors a heterochiral arrangement stabilized by both normal and bifurcated H-bonds, rather than the common binding topology with a cyclic OH⋅⋅⋅OH bonded ring that is adopted by trimers of water and other related alcohol molecules. The role of transient chirality and the strength of the bifurcated H-bonds were investigated.
Time-Resolved Crystallography of the Reaction Intermediate of Nitrile Hydratase: Revealing a Role for the Cysteinesulfenic Acid Ligand as a Catalytic Nucleophile
Dr. Yasuaki Yamanaka, Dr. Yuki Kato, Dr. Koichi Hashimoto, Dr. Keisuke Iida, Prof. Kazuo Nagasawa, Dr. Hiroshi Nakayama, Dr. Naoshi Dohmae, Prof. Keiichi Noguchi, Prof. Takumi Noguchi, Prof. Masafumi Yohda and Prof. Masafumi Odaka
Visualizing enzyme reactions: The catalytic reaction of nitrile hydratase is monitored by time-resolved crystallography (see picture; C gray, N blue, O red, S yellow, Fe orange). Upon light-induced release of NO, the substrate observed in the pocket turned to bind to the Fe ion to form a cyclic reaction intermediate. The structure of the intermediate shows that the coordinated substrate is attacked by the sulfenate ligand.
Selective Synthesis of Single- and Multi-Walled Supramolecular Nanotubes by Using Solvophobic/Solvophilic Controls: Stepwise Radial Growth via “Coil-on-Tube” Intermediates
Dr. Seelam Prasanthkumar, Dr. Wei Zhang, Prof. Dr. Wusong Jin, Prof. Dr. Takanori Fukushima and Prof. Dr. Takuzo Aida
Coiled for action: The hierarchical assembly of hexabenzocoronene derivatives with perfluoroalkyl segments can be controlled by solvophobic and solvophilic effects. This control enables the selective synthesis of single- and multi-walled nanotubes. Increasing the number of walls occurs via coil-on-tube intermediates.
Silver-Mediated Oxidative Trifluoromethylation of Phenols: Direct Synthesis of Aryl Trifluoromethyl Ethers
Jian-Bo Liu, Dr. Chao Chen, Dr. Lingling Chu, Dr. Zeng-Hao Chen, Dr. Xiu-Hua Xu and Prof. Dr. Feng-Ling Qing
Combining two nucleophiles: The direct oxidative O-trifluoromethylation of phenols with CF3SiMe3 provides a general and practical method for the preparation of aryl trifluoromethyl ethers. A wide variety of functional groups are tolerated under these conditions, and the method can also be employed for the late-stage trifluoromethylation of complex pharmaceutically relevant molecules (NFSI= N-fluorobenzenesulfonimide).
Detection of the Short-Lived Radical Cation Intermediate in the Electrooxidation of N,N-Dimethylaniline by Mass Spectrometry
Timothy A. Brown, Prof. Hao Chen and Prof. Richard N. Zare
Now you see it: The N,N-dimethylaniline radical cation DMA.+, a transient intermediate with a half-life shorter than 1 μs, was detected by mass spectrometry (MS) during the electrochemical oxidation of DMA by coupling desorption electrospray ionization (DESI)-MS with a waterwheel working electrode system.
Finely Tuned Polymer Interlayers Enhance Solar Cell Efficiency
Dr. Yao Liu, Zachariah A. Page, Prof. Dr. Thomas P. Russell and Prof. Dr. Todd Emrick
Organic electronics: Three conjugated polymer zwitterions of variable bandgap were synthesized and incorporated as cathode modification layers in bulk heterojunction solar cells, boosting the power conversion efficiency (PCE) to over 10 %. Structure–property relationships identified key optical and electronic characteristics that lead to the observed high efficiencies.
Highly Ordered Nanoporous Films from Supramolecular Diblock Copolymers with Hydrogen-Bonding Junctions
Dr. Damien Montarnal, Dr. Nicolas Delbosc, Cécile Chamignon, Dr. Marie-Alice Virolleaud, Yingdong Luo, Prof. Craig J. Hawker, Prof. Eric Drockenmuller and Dr. Julien Bernard
Link for a minute: Supramolecular diblock copolymers self-assemble from high molecular weight polymers bearing complementary strong hydrogen-bonding groups. Hierarchical organization affords thin films with excellent lateral order that can be readily transformed into porous membranes, without any degradation, by disruption of the supramolecular links with water/alcohol solutions.
Palladium-Catalyzed Decarbonylative Dehydration for the Synthesis of α-Vinyl Carbonyl Compounds and Total Synthesis of (−)-Aspewentins A, B, and C
Yiyang Liu, Dr. Scott C. Virgil, Prof. Robert H. Grubbs and Prof. Brian M. Stoltz
Vinyl unveiled: It is described that δ-oxocarboxylic acids can serve as masked vinyl compounds and be unveiled by Pd-catalyzed decarbonylative dehydration to enable the α-vinylation of carbonyl compounds to form a quaternary stereocenter. A variety of α-vinyl quaternary carbonyl compounds are obtained in good yields, and an application in the first enantioselective total synthesis of (−)-aspewentins A–C is demonstrated.
Self-Pillared, Single-Unit-Cell Sn-MFI Zeolite Nanosheets and Their Use for Glucose and Lactose Isomerization
Dr. Limin Ren, Dr. Qiang Guo, Prashant Kumar, Marat Orazov, Dandan Xu, Prof. Saeed M. Alhassan, Prof. K. Andre Mkhoyan, Prof. Mark E. Davis and Prof. Michael Tsapatsis
The adventures of thin tin: Sn is introduced in the framework of single-unit-cell (2 nm thick) zeolite MFI lamellae, which are intergrown in a self-pillared arrangement to obtain a hierarchical micro/mesoporous Lewis acid catalyst. Its conversion and selectivity are better than those of other micro- and mesoporous Sn-containing catalysts for isomerization of mono- and di-sacharides.