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  • Rational Design of a 310‐Helical PIP‐Box Mimetic Targeting PCNA, the Human Sliding Clamp
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Kate L. Wegener; Amy E. McGrath; Nicholas E. Dixon; Aaron J. Oakley; Denis B. Scanlon; Andrew D. Abell; John B. Bruning
    更新日期:2018-07-20
  • Intra‐ and Interparticle Heterogeneities in Solid Activators for Single‐Site Olefin Polymerization Catalysis as Revealed by Micro‐Spectroscopy
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Marjolein E. Z. Velthoen; Johannes D. Meeldijk; Florian Meirer; Bert M. Weckhuysen
    更新日期:2018-07-20
  • Ionic Co‐Crystal Formation as a Path Towards Chiral Resolution in the Solid State
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Oleksii Shemchuk; Boryana K. Tsenkova; Dario Braga; M. Teresa Duarte; Vânia André; Fabrizia Grepioni
    更新日期:2018-07-20
  • 更新日期:2018-07-20
  • 更新日期:2018-07-20
  • 更新日期:2018-07-20
  • Chemoenzymatic Route to Oxyfunctionalized Cembranoids Facilitated by Substrate and Protein Engineering
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-04
    Priska Le‐Huu; Dominik Rekow; Claudia Krüger; Ansgar Bokel; Tanja Heidt; Sebastian Schaubach; Birgit Claasen; Sebastian Hölzel; Wolfgang Frey; Sabine Laschat; Vlada B. Urlacher
    更新日期:2018-07-20
  • A Nanosized Phenylene‐Ethynylene‐Butadiynylene [2]Catenane
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-02
    Christopher Schweez; Sigurd Höger
    更新日期:2018-07-20
  • Selective Synthesis of Unsymmetrical Aliphatic Acyloins through Oxidation of Iridium Enolates
    Chem. Eur. J. (IF 5.16) Pub Date : 18 July 20
    Amparo Sanz‐Marco; Samuel Martinez‐Erro; Belén Martín‐Matute
    更新日期:2018-07-20
  • Rational Design of a 310‐Helical PIP‐Box Mimetic Targeting PCNA, the Human Sliding Clamp
    Chem. Eur. J. (IF 5.16) Pub Date : 19 July 20
    Kate L. Wegener; Amy E. McGrath; Nicholas E. Dixon; Aaron J. Oakley; Denis B. Scanlon; Andrew D. Abell; John B. Bruning
    更新日期:2018-07-20
  • 更新日期:2018-07-20
  • Chromium Complexes with Oxido and Corrolato Ligands: Metal‐Based Redox Processes versus Ligand Non‐Innocence
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-08
    Antara Garai; Sebastian Sobottka; Rahel Schepper; Woormileela Sinha; Matthias Bauer; Biprajit Sarkar; Sanjib Kar
    更新日期:2018-07-20
  • Topology‐Selective, Fluorescent “Light‐Up” Probes for G‐Quadruplex DNA Based on Photoinduced Electron Transfer
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-07
    Xiao Xie; Oksana Reznichenko; Ludovic Chaput; Pascal Martin; Marie‐Paule Teulade‐Fichou; Anton Granzhan
    更新日期:2018-07-20
  • meso‐Functionalization of Boron(III) Subporphyrin with Boron(III) meso‐Lithiosubporphyrin
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-07
    Yosuke Bekki; Daiki Shimizu; Keisuke Fujimoto; Atsuhiro Osuka
    更新日期:2018-07-20
  • Electron Flow in Large Metallomacromolecules and Electronic Switching of Nanoparticle Stabilization: Click Ferrocenyl Dentromers that Reduce AuIII to Au Nanoparticles
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-04
    Qi Wang; Fangyu Fu; Angel M. Martinez‐Villacorta; Sergio Moya; Lionel Salmon; Amélie Vax; Julien Hunel; Jaime Ruiz; Didier Astruc
    更新日期:2018-07-20
  • 更新日期:2018-07-20
  • Activation of O‐H and C‐O Bonds in Water and Methanol by a Vanadium‐bound Thiyl Radical
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Jyun-An Yan; Zi-Kuan Yang; Yu-Sen Chen; Ya-Ho Chang; Chiao-Ling Lyu; Chun-Gang Luo; Mu-Jeng Cheng; Hua-Fen Hsu

    The reaction of [V(PS3")]‐ (1) (PS3" = [P(C6H3‐3‐Me3Si‐2‐S)3]3‐) with H2O led to the formation of [VIV(PS3")(PS2"SH)] (2) (PS2"SH = [P(C6H3‐3‐Me3Si‐2‐S)2(C6H3‐3‐Me3Si‐2‐SH)]2‐), indicating a hydrogen atom transfer from H2O to a bound thiolate in 1. Furthermore, the reaction of 1 with CH3OH gave the generation of complex 2 and [VIV(PS3")(PS2"SCH3)] (3) (PS2"SCH3 = [P(C6H3‐3‐Me3Si‐2‐S)2(C6H3‐3‐Me3Si‐2‐SCH3)]2‐), implying that C‐O and O‐H bonds are cleaved by 1. Quantum mechanical calculations were performed to provide the mechanistic understanding for the reactivity of 1 with water. A key transition state with a lower kinetic barrier is identified. It involves an O‐H bond cleavage by a dissociated thiyl radical with an interaction between an OH group and a neighboring bound sulfur donor. To our knowledge, the reactivity of 1 represents a new mode for water activation conducted through cooperation between a metal‐stabilized thiyl radical and a neighboring thiolato donor.

    更新日期:2018-07-20
  • Fluorescent sulphur and nitrogen containing porous polymers with tuneable donor‐acceptor domains for light‐driven hydrogen evolution
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Dana Schwarz; Amitava Acharjya; Arun Ichangi; Pengbo Lyu; Maksym V. Opanasenko; Fabian R. Goßler; Tobias F. König; Jiří Čejka; Petr Nachtigall; Arne Thomas; Michael Janus Bojdys

    Light‐driven water splitting is a potential source of abundant, clean energy, yet efficient charge‐separation and size and position of the bandgap in heterogeneous photocatalysts are challenging to predict and design. Synthetic attempts to tune the bandgap of polymer photocatalysts classically rely on variations of the sizes of their π‐conjugated domains. However, only donor‐acceptor dyads hold the key to prevent undesired electron‐hole recombination within the catalyst via efficient charge separation. Building on our previous success in incorporating electron‐donating, sulphur‐containing linkers and electron‐withdrawing, triazine (C3N3) units into porous polymers, we report the synthesis of six visible‐light active, triazine‐based polymers with a high heteroatom‐content of S and N that photocatalytically generate H2 from water: up to 915 µmol h‐1 g‐1 with Pt co‐catalyst, and ‐ as one of the highest to‐date reported values ‐ 200 µmol h‐1 g‐1 without. The highly modular Sonogashira‐Hagihara cross‐coupling reaction we employ, enables a systematic study of mixed (S, N, C) and (N, C)‐only polymer systems. Our results highlight that photocatalytic water‐splitting does not only require an ideal optical bandgap of ~2.2 eV, but that the choice of donor‐acceptor motifs profoundly impacts charge‐transfer and catalytic activity.

    更新日期:2018-07-20
  • Designing for Cross‐coupling Reactions Using Aryl(trialkyl)silanes
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Yasunori Minami; Tamejiro Hiyama

    Organo(trialkyl)silanes have advantages in view of stability, low toxicity, solubility, handling, and ready availability compared with heteroatom‐substituted silanes. On the other hand, cross‐coupling with organo(trialkyl)silanes has been limited probably because of the exceeding robustness. Thus, a practical cross‐coupling method with organo(trialkyl)silanes has been a long‐standing challenging research target. This article discusses the designing how to use aryl(trialkyl)silanes for the cross‐coupling. A pioneering example is Cu(II)‐catalytic conditions using electron‐accepting aryl‐ or heteroaryl(triethyl)silanes and aryl iodides. The reaction forms biaryls or teraryls. This design concept is extended to Pd/Cu(II)‐catalyzed cross‐coupling and polymerization between such silanes and aryl bromides or chlorides and Cu(I)‐catalyzed alkylation using alkyl halides.

    更新日期:2018-07-20
  • Recent progress of nickel‐based oxide/(oxy)hydroxide electrocatalysts for oxygen evolution reaction
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Yaping Chen; Kun Rui; Jixin Zhu; Shi Xue Dou; Wenping Sun

    Developing clean and sustainable energies as alternatives to fossil fuels is highly demanded by the modern society. Oxygen evolution reaction (OER) is the efficiency‐limiting process in plenty of key renewable energy systems, such as electrochemical water splitting and rechargeable metal‐air batteries. In this regard, ongoing efforts have been devoted to seeking high‐performance electrocatalysts for enhanced energy‐conversion efficiency. Apart from traditional precious metal‐based catalysts, nickel‐based compounds are the most promising earth‐abundant OER catalysts, attracting ever‐increasing interest due to high activity and stability. In this review, we summarize the recent progress on nickel‐based oxide and (oxy)hydroxide composites for water oxidation catalysis in terms of materials design/synthesis and electrochemical performance. We also highlight some underlying mechanisms to profoundly understand the catalytic active sites. In addition, the future research trends and perspectives on the development of Ni‐based OER electrocatalysts are discussed.

    更新日期:2018-07-20
  • Isolated collagen mimetic peptide assemblies have stable triple‐helix structures
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Mathieu Lalande; Clothilde Comby-Zerbino; Mathilde Bouakil; Philippe Dugourd; Fabien Chirot; Jean-Christophe Poully

    The origin of the triple‐helix structure and high stability of collagen has been debated for many years. As models of the triple helix and building blocks for new biomaterials, collagen mimetic peptide (CMP) assemblies have been deeply studied in the condensed phase. In particular, it was found that hydroxylation of proline, an abundant post‐translational modification in collagen, increases its stability. Two main hypotheses emerged to account for this behavior: 1) intra‐helix stereoelectronic effects, and 2) the role of water molecules H‐bound to hydroxyproline side‐chains. However, in condensed‐phase investigations, the influence of water cannot be fully removed. Therefore, we employed a combination of tandem ion mobility and mass spectrometries to assess the structure and stability of CMP assemblies in the gas phase. Our results show a conservation of the structure and stability properties of triple helix models in the absence of solvent, supporting an important role of stereoelectronic effects. Moreover, we give evidence that small triple helix assemblies with controlled stoichiometry can be studied in the gas phase, which opens new perspectives in the understanding of the first steps of collagen fiber growth.

    更新日期:2018-07-20
  • Effects of temperature on the shape and symmetry of molecules and solids
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Abel Carreras; Efrem Bernuz; Xavier Marugan; Miquel Llunell; Pere Alemany

    Despite its undeniable problems from a philosophical point of view, the concept of molecular structure, with attributes such as shape and symmetry, directly borrowed from the description of macroscopic objects, is nowadays central to most of the chemical sciences. Descriptions such as "the tetrahedral" carbon atom or "octahedral coordination complexes" are widely used as much in elementary textbooks as in the most up‐to‐date research articles. The definition of molecular shape is, however, not as simple as it might seem at first sight. Molecules don't behave as macroscopic objects do, and the arrangement of atoms within a molecule changes continuously due to the incessant motion of its constituent particles, nuclei and electrons. How are molecular shape and symmetry affected by this thermal motion? In this review we introduce the language of continuous symmetry measures as a new tool to quantitatively describe the effects of temperature on molecular shape and symmetry, enriching in this way the set of molecular descriptors that might be used in the establishment of new empirical structure‐property relations, of great interest in concomitant areas such as medicinal chemistry or materials science.

    更新日期:2018-07-20
  • Synthesis and Characterization of Self‐Assembled Chiral FeII2L3 Cages
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-19
    Bin Sun; Sandra Nurttila; Joost Reek

    We present here the synthesis of chiral BINOL derived bisamine and bispyridine‐aldehyde building blocks that can be used for the self‐assembly of novel chiral FeII2L3 cages when mixed with an Fe(II) precursor. The properties of a series of chiral cages were studied by NMR, CSI‐MS and CD spectroscopy and molecular modelling. Upon formation of the M2L3 cages the iron corners can adopt various isomeric forms: mer, fac‐Δ or fac‐Λ. We found that the coordination geometry around the metal centers in R‐Cage 1 and 2, are influenced by the chiral BINOL backbone only to a limited extent, as a mixture of cages are formed with fac‐ and mer‐ configurations at the iron corners. However, single cage species (fac‐RR‐Cage and fac‐RS‐Cage) that are enantiopure and highly symmetric were obtained by generating these chiral M2L3 cages using the bispyridine‐aldehyde building blocks in combination with chiral amine moieties to form the pyridylimine ligands for coordination to iron. Next to consistent NMR spectra, CD spectra confirm the configurations fac‐ (Λ,Λ) or fac‐(Δ,Δ) corresponding to the RR‐ and RS‐Cage, respectively.

    更新日期:2018-07-20
  • A Porous Framework as a Variable Chemosensor: From the Response of a Specific Carcinogenic Alkyl‐Aromatic to Selective Detection of Explosive Nitroaromatics
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Hui Xue; Danhua Song; Caiping Liu; Guangxun Lyu; Daqiang Yuan; Feilong Jiang; Qihui Chen; Maochun Hong
    更新日期:2018-07-19
  • Formation and Extractive Desulfurization Mechanisms of Aromatic Acid Based Deep Eutectic Solvents: An Experimental and Theoretical Study
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Xiuxiu Zhao; Guoqiang Zhu; Lingying Jiao; Fengli Yu; Congxia Xie
    更新日期:2018-07-19
  • Crystal Structure and Magnetic Properties of ϵ‐RuxFe2‐xO3 Nanosize Hard Ferrite
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-04
    Asuka Namai; Shin‐ichi Ohkoshi
    更新日期:2018-07-19
  • Mesoscopic FRET Antenna Materials by Self‐Assembling Iridium(III) Complexes and BODIPY Dyes
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-02
    Andrew J. Bagnall; Marina Santana Vega; Jonathan Martinelli; Kristina Djanashvili; Fabio Cucinotta
    更新日期:2018-07-19
  • Luminescence from Lanthanide(III) Ions Bound to the Glycocalyx of Chinese Hamster Ovary Cells
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-25
    Riikka Arppe‐Tabbara; Miguel R. Carro‐Temboury; Casper Hempel; Tom Vosch; Thomas Just Sørensen
    更新日期:2018-07-19
  • Chemoselective Tyrosine Bioconjugation through Sulfate Click Reaction
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-23
    Eun Joung Choi; Dongwook Jung; Jong‐Seo Kim; Yan Lee; B. Moon Kim
    更新日期:2018-07-19
  • Lewis‐Base‐Induced Disproportionation of a Dialane
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-19
    Alexander Hofmann; Anna Lamprecht; J. Oscar C. Jiménez‐Halla; Tobias Tröster; Rian D. Dewhurst; Carsten Lenczyk; Holger Braunschweig
    更新日期:2018-07-19
  • 更新日期:2018-07-19
  • Copper‐Mediated Trifluoromethylation of Benzylic Csp3−H Bonds
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-15
    Matthew Paeth; William Carson; Jheng‐Hua Luo; David Tierney; Zhi Cao; Mu‐Jeng Cheng; Wei Liu
    更新日期:2018-07-19
  • Positional Isomers of Chromophore–Peptide Conjugates Self‐Assemble into Different Morphologies
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-12
    Urszula Lewandowska; Stefano Corra; Wojciech Zajaczkowski; Nellie A. K. Ochs; Michal S. Shoshan; Junki Tanabe; Sebastian Stappert; Chen Li; Eiji Yashima; Wojciech Pisula; Klaus Müllen; Helma Wennemers
    更新日期:2018-07-19
  • Electron Delocalization of Mixed‐Valence Diiron Sites Mediated by Group 10 Metal Ions in Heterotrimetallic Fe‐M‐Fe (M=Ni, Pd, and Pt) Chain Complexes
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-11
    Yu‐Chiao Liu; Shao‐An Hua; Ming‐Chuan Cheng; Li‐Chung Yu; Serhiy Demeshko; Sebastian Dechert; Franc Meyer; Gene‐Hsiang Lee; Ming‐Hsi Chiang; Shie‐Ming Peng
    更新日期:2018-07-19
  • A Porous Framework as a Variable Chemosensor: From the Response of a Specific Carcinogenic Alkyl‐Aromatic to Selective Detection of Explosive Nitroaromatics
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-07
    Hui Xue; Danhua Song; Caiping Liu; Guangxun Lyu; Daqiang Yuan; Feilong Jiang; Qihui Chen; Maochun Hong
    更新日期:2018-07-19
  • Formation and Extractive Desulfurization Mechanisms of Aromatic Acid Based Deep Eutectic Solvents: An Experimental and Theoretical Study
    Chem. Eur. J. (IF 5.16) Pub Date : 18 July 20
    Xiuxiu Zhao; Guoqiang Zhu; Lingying Jiao; Fengli Yu; Congxia Xie
    更新日期:2018-07-19
  • Helicity Control of Triphenylamine‐Based Supramolecular Polymers: Correlation between Solvent Properties and Helicity in Supramolecular Gels
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-05-30
    Ka Young Kim; Chaelin Kim; Yeonweon Choi; Sung Ho Jung; Ju Hyun Kim; Jong Hwa Jung
    更新日期:2018-07-19
  • Nucleophilic Influences and Origin of the SN2 Allylic Effect
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-05-27
    Boris Galabov; Gergana Koleva; Henry F. Schaefer; Wesley D. Allen
    更新日期:2018-07-19
  • Investigating the low temperature formation of CuII‐(N,O) species on Cu‐CHA zeolites for the Selective Catalytic Reduction of NOx
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Chiara Negri; Peter Sams Hammershøi; Ton V.W. Janssens; Pablo Beato; Gloria Berlier; Silvia Bordiga

    In this work, we show the potentiality of operando FTIR spectroscopy to follow the formation of CuII‐(N,O) species on Cu exchanged chabazite zeolites (Cu‐CHA), active for the selective catalytic reduction of NOx with NH3 (NH3‐SCR). In particular, we investigated the reaction of NO and O2 at low temperature (200 and 50 °C) on a series of Cu‐CHA zeolites with different composition (Si/Al and Cu/Al ratios), to investigate the nature of the formed copper nitrates, which have been proposed to be key intermediates in the oxidation part of the SCR cycle. Our results show that chelating bidentate nitrates are the main structures formed at 200 °C. At lower temperature a mixture of chelating and monodentate nitrates are formed, together with the nitrosonium ion NO+., whose amount was found to be proportional to the zeolites Brønsted sites concentration. Nitrates were found to mainly form with CuII ions stabilized by one negative framework charge (Z), Z‐[Cu(OH]I or Z‐[Cu(O2]I, without involvement of Z2‐CuII ones. This evidence, together with the absence of bridging nitrates in samples with high probability for Cu‐Cu pairs, indicate that the nitrate ligands are not able to mobilize copper ions, at variance with what recently reported for NH3. Finally, water was found to replace preformed chelating copper nitrates and deplete NO+ (though with different kinetics) at both temperatures, while favouring the presence of monodentate ones.

    更新日期:2018-07-19
  • Bridge‐Caging Strategy in Phosphorus‐Substituted Rhodamine for Modular Development of Near‐Infrared Fluorescent Probes
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Xiaoyun Chai; Jin Xiao; Min Li; Chaoming Wang; Haiyan An; Chen Li; Yuntao Li; Dazhi Zhang; Xiaoyan Cui; Ting Wang

    Replacement of the bridging oxygen atom with phosphorus in rhodamine is one of the most efficient ways for bright near‐infrared (NIR) fluorophores with wavelength over 700 nm. However, the organophosphorus bridge is more versatile than being a spectrum‐tuner, it is also a profound solubility‐booster and photostability‐enhancer, as proved by a series of phosphorus‐substituted rhodamines (PRBs). A unique bridge‐caging strategy for efficiently manipulating fluorescence has further been innovated in the exemplary PRB2. Consistent with theoretical calculation, the formation of organo‐phosphinate by caging group as fluorescence‐controller locks the spirolactone into colorless and non‐fluorescent form, while the decaging process after specific stimulus has resulted in ring‐opened form, yielding strong fluorescence. The bridge‐caging strategy is feasible for modular development of NIR probes. Efficient in vivo imaging of photo‐illumination, hydrogen peroxide and enzyme have been achieved on the PRB2 scaffold as photoactivatable fluorophore PRB2‐hν, fluorescent indicator PRB2‐H2O2 and fluorogenic enzyme substrate PRB2‐NTR.

    更新日期:2018-07-19
  • Extremely Long‐lived Localized Singlet Diradicals in a Macrocyclic Structure: A Case Study of the Stretch Effect
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Manabu Abe; Yuta Harada; Zhe Wang; Sayaka Hatano; Shunsuke Kumashiro

    Localized singlet diradicals have attracted much attention not only in the field of bond‐homolysis chemistry, but also in non‐linear optical materials. In this study, an extremely long‐lived localized singlet diradical emerged using a new molecular design‐a macrocyclic structural effect‐that is kinetically stabilized by increasing the molecular strain of the corresponding σ‐bonded product. Notably, the lifetime of this diradical (14 μs) is two‐orders of magnitude longer than that of a standard singlet diradical without a macrocyclic structure (~0.2 μs) at 293 K. The species is persistent at below the temperature of 100 K. In addition to the kinetic stabilization of the singlet diradical, the spontaneous oxidation of its corresponding ring‐closed compound at 298 K produced oxygenated products under atmospheric conditions. Apparently, the "stretch effect" induced by the macrocyclic structure plays a crucial role in extending the lifetime of localized singlet diradicals and increasing the reactivity of their corresponding σ‐bonded products.

    更新日期:2018-07-19
  • Synthesis of lipid‐carbohydrate‐peptidyl‐RNA conjugates to explore the limits imposed by the substrate specificity of cell wall enzymes on the acquisition of drug resistance
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Matthieu Fonvielle; Ahmed Bouhss; Coralie Hoareau; Delphine Patin; Dominique Mengin-Lecreulx; Laura Iannazzo; Nicolas Sakkas; Affaf El Sagheer; Tom Brown; Mélanie Ethève-Quelquejeu; Michel Arthur

    Conjugation of RNA with multiple partners to obtain mimics of complex biomolecules is limited by the identification of orthogonal reactions. Here, lipid‐carbohydrate‐peptidyl‐RNA conjugates were obtained by post‐functionalization reactions, solid‐phase synthesis, and enzymatic steps, to generate molecules mimicking the substrates of FmhB, an essential peptidoglycan synthesis enzyme of Staphylococcus aureus. Mimics of Gly‐tRNAGly and lipid intermediate II (undecaprenyl‐diphospho‐disaccharide‐pentapeptide) were combined in a single "bi‐substrate" inhibitor (IC50 = 56 nm). The synthetic route was exploited to generate substrates and inhibitors containing D‐Lac instead of D‐Ala at the C‐terminus of the pentapeptide stem, a modification responsible for vancomycin resistance in the enterococci. The substitution impaired recognition of peptidoglycan precursors by FmhB. The associated fitness cost may account for limited dissemination of vancomycin resistance genes in S. aureus.

    更新日期:2018-07-19
  • Mechanochromic Switching between Delayed Fluorescence and Phosphorescence of Luminescent Coordination Polymers Composed of Dinuclear Copper(I) Iodide Rhombic Cores
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Atsushi Kobayashi; Yuya Yoshida; Masaki Yoshida; Masako Kato

    The synthesis and photophysical properties of two luminescent Cu(I) coordination polymers, [Cu2I2(PPh3)2(3‐tpyb)]n and [Cu2I2(PPh3)2(4‐tpyb)]n (Cu‐3‐tpyb and Cu‐4‐tpyb; PPh3 = triphenylphosphine, m‐tpyb = 1,3,5‐tris(n‐pyridyl)benzene (m = 3, 4)), are described. X‐ray structural analysis indicated that one‐dimensional coordination chains comprising rhombic {Cu2I2(PPh3)2} cores and m‐tpyb bridging ligands were formed. Both Cu‐3‐tpyb and Cu‐4‐tpyb exhibited blue‐to‐yellow thermally activated delayed fluorescence (TADF) that originated from mixing of the metal‐to‐ligand and halide‐to‐ligand charge‐transfer excited states and moderate emission quantum yields of 0.29 and 0.27, respectively, at 298 K. Further, mechanochromic luminescence was observed for both complexes. The emission lifetimes indicated that the origin of emission switched from TADF to phosphorescence, which was derived from the triplet cluster‐centred (3CC) emissive state generated by grinding‐induced amorphization.

    更新日期:2018-07-19
  • Decarboxylative Organocatalytic Allylic Amination of Morita‐Baylis‐Hillman Carbamates
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Vojtěch Dočekal; Michal Šimek; Martin Dračínský; Jan Vesely

    The present study reports the organocatalytic asymmetric allylic amination of Morita‐Baylis‐Hillman carbamates efficiently catalyzed with chiral amine in the presence of Brønsted acid. Chiral allylic amines were produced in high yields (up to 98%) and enantioselectivities (up to 97% ee). This method provides an efficient and easily‐performed route to prepare α‐methylene‐β‐lactams, and other optically active β‐lactams, such as the cholesterol‐lowering drug Ezetimibe.

    更新日期:2018-07-19
  • A Visible Light‐Induced Strategy to Construct Osmanaphthalynes, Osmaanthracyne and Osmaphenanthryne
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Shenghua Liu; Ming-Xing Zhang; Zhiqiang Xu; Tao Lu; Jun Yin

    Herein, we describe a novel, green and efficient synthesis of a series of different substituted osmanaphthalynes (including −H, −Br, −I, −CH3 and −CF3) and the first examples of the preparation of α‐osmaanthracyne and α‐osmaphenanthryne by means of a visible light‐induced intramolecular cyclization reaction of their corresponding osmium hydrido alkenylcarbyne complexes. This visible‐light‐driven method provides an efficient and straightforward approach to afford the desired fused metal heterocyclic complexes constructed with an Os atom as the metal center in high yield under mild conditions.

    更新日期:2018-07-19
  • A novel family of polyiodo‐bromoantimonate(III) complexes: cation‐driven self‐assembly of photoconductive metal‐polyhalide frameworks
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Sergey A. Adonin; Liubov Udalova; Pavel Abramov; Alexander Novikov; Irina Yushina; Ilya Korolkov; Evgeniy Semitut; Tatiyana Derzhavskaya; Keith Stevenson; Pavel Troshin; Maxim Sokolov; Vladimir Fedin

    In presence of different cations, reactions of [SbBr6]3‐ and I2 result in a new family of diverse supramolecular 1D polyiodide‐bromoantimonate networks. Coordination number of Sb, as well as geometry of assembling {Ix}n‐ polyhalide units, can vary, resulting in unprecedented structural types. The nature of I···Br interactions was studied by DFT calculations; estimated energy values are 1.6‐6.9 kcal/mol. Some of the compounds showed strong photoconductivity in thin films, suggesting multiple feasible applications in optoelectronics and solar energy conversion.

    更新日期:2018-07-19
  • Fluorooxoborates: Ushering in a New Era of Deep Ultraviolet Nonlinear Optical Materials
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Guopeng Han; Ying Wang; Bingbing Zhang; Shilie Pan

    Borates are one of the most important classes of functional materials, and several hundreds of artificial borates have been synthesized. The substitution of oxygen by fluorine leads to manifold class of borates. Fluorooxoborates (also known as fluoroborate), in which the F atoms covalently connect with the B atoms, show additional compositional and structural diversity compared to classic borates. Recently, owing to the large polarizability anisotropy, large HOMO‐LUMO gaps, and high hyperpolarizability of the oxyfluoride BOxF4‐x building blocks, fluorooxoborates have received unprecedented attention to search new ultraviolet (UV) and deep‐UV (DUV) nonlinear optical (NLO) materials. Specifically, these compounds have excellent NLO properties that are comparable or superior to KBe2BO3F2, which is the only usable crystal that generates coherent light below 200 nm through a direct second harmonic generation (SHG) process. This minireview illustrates recent progress on the synthesis, crystal structures, structure‐properties relationships and applications of fluorooxoborates. We conclude this paper by highlighting the outstanding opportunities offered by NLO fluorooxoborate crystals as innovative avenue for DUV all solid‐state coherent light generation.

    更新日期:2018-07-19
  • Commercially‐relevant orthogonal multi‐component supramolecular hydrogels for programmed cell growth
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Vania Vieira; Ana Lima; Menno de Jong; David K. Smith

    This paper reports the ability of synthetically‐simple, commercially‐viable sugar‐derived 1,3:2,4‐dibenzylidenesorbitol‐4',4"‐diacylhydrazide (DBS‐CONHNH2) to support cell growth. Simple mixing and orthogonal self‐sorting can formulate heparin, agarose, and heparin‐binding micelles into these gels ‐ easily incorporating additional function. Interestingly, the components used in the gel formulation, direct the ability of cells to grow, meaning the chemical programming of these multi‐component gels is directly translated to the biological systems in contact with them. This simple approach has potential for future development in regenerative medicine.

    更新日期:2018-07-19
  • [3,3]‐Sigmatropic Rearrangement of Cyclopropenylcarbinyl Cyanates. Access to Alkylidene(aminocyclopropane) Derivatives
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Guillaume ERNOUF; Jean-Louis BRAYER; Benoît FOLLEAS; Jean-Pierre DEMOUTE; Christophe Meyer; Janine COSSY

    Cyclopropenylcarbinyl cyanates, generated in situ by dehydration of the corresponding carbamates, undergo an efficient and stereoselective [3,3]‐sigmatropic rearrangement leading to the corresponding alkylidene(isocyanatocyclopropanes) that can be converted into various alkylidene(aminocyclopropane) derivatives in a one‐pot manner. This transformation complements the repertoire of sigmatropic rearrangements involving cyclopropenylcarbinol derivatives and in particular the previously reported Overman rearrangement of cyclopropenylcarbinyl trichloroacetimidates.

    更新日期:2018-07-19
  • Non‐Covalently Pre‐Assembled High‐Performance Near‐Infrared Fluorescent Molecular Probes for Cancer Imaging
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    Scott Shaw; Wenqi Liu; César Fernando Azael Gómez Durán; Cynthia Schreiber; María de Lourdes Betancourt Mendiola; Canjia Zhai; Felicia Roland; Simon Padanilam; Bradley D. Smith

    Fluorescent molecular probes were prepared by a programmed non‐covalent pre‐assembly process that used a near‐infrared fluorescent squaraine dye to thread a macrocycle bearing a cancer targeting unit. Cell microscopy studies using OVCAR‐4 (ovarian cancer) and A549 (lung cancer) cells that express high levels of the integrin αvβ3 or αvβ5 receptors, respectively, revealed a multivalent cell targeting effect. That is, there was comparatively more cell uptake of a pre‐assembled probe equipped with two copies of the cRGDfK antagonist than a pre‐assembled probe with only one appended cRGDfK antagonist. The remarkably high photostability and low phototoxicity of these near‐infrared probes allowed acquisition of long‐term fluorescence movies showing endosome trafficking in living cells. In vivo near‐infrared fluorescence imaging experiments compared the biodistribution of a targeted and untargeted probe in a xenograft mouse tumor model. The average tumor‐to‐muscle ratio for the pre‐assembled targeted probe was 3.6 which matches the tumor targeting performance reported for analogous cRGDfK‐based probes that were prepared entirely by covalent synthesis. The capability to excite these pre‐assembled near‐infrared fluorescent probes with blue or deep‐red excitation light makes it possible to determine if a target site is located superficially or buried in tissue, a probe performance feature that is likely to be very helpful for eventual applications such as fluorescence guided surgery.

    更新日期:2018-07-19
  • Bifunctional Separator Coated by Hexachlorocyclotriphosphazene/rGO for Enhanced Performance of Li−S Batteries: Investigated Experimentally and Theoretically
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-18
    yanping zheng; honghong fan; huanhuan li; chaoying fan; haiyan yuan; zhifang yang; kecheng huang; wenliang li; Jingping Zhang

    Although extensive research has been performed in the field of Li‐S rechargeable batteries, the commercial applications are still hindered by the dissolution of the reaction intermediates of lithium polysulfides (LiPSs). With the combination of experimental and the theoretical approach, a bifunctional separator is designed by coating hexachlorocyclotriphosphazene (HCCP) decorated rGO, which provides effective anchor sites for immobilizing the LiPSs. LiPSs can be adsorbed on the HCCP/rGO surface with moderate binding strength, and their structures as well as the electrical conductivity of HCCP/rGO are well maintained. Synergetic effect of the effective barrier and good electrical conductivity within the HCCP/rGO sheets efficiently anchors the LiPSs and achieves enhanced electrochemical performance. More importantly, different substituents can be used to tune the immobilization of LiPSs by HCCP derivatives. Therefore, it is expected that HCCP and its derivatives can be utilized as the promising anchoring material for high performance Li‐S batteries.

    更新日期:2018-07-19
  • Monomeric Rare‐earth Metal Silyl‐Thiophosphinoyl‐Alkylidene Complexes: Synthesis, Structure and Reactivity
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Yaofeng Chen; Chen Wang; Li Xiang; Yan Yang; Jian Fang; Laurent Maron; Xuebing Leng; Weiqing Mao

    A series of monomeric rare‐earth metal silyl‐thiophosphinoyl‐alkylidene complexes [LLn{C(SiR3)PPh2S}] (L = [MeC(NDIPP)CHC(Me)(NCH2CH2N(Me)2)]−, DIPP = 2,6‐(iPr)2C6H3; 5: Ln = Lu, R = Me; 6: Ln = Lu, R = Ph; 7: Ln = Y, R = Me; 8: Ln = Y, R = Ph; 9: Ln = Sm, R = Ph; 10: Ln = Sm, R = Me; 11: Ln = La, R = Ph) were synthesized and structurally characterized. The influences of rare‐earth metal ions, ancillary ligands and alkylidene groups on the reactivity of complexes 5 ‒ 11 and the related scandium complexes [LSc{C(SiR3)PPh2S}] (1: R = Me; 2: R = Ph) and [LʹSc{C(SiR3)PPh2S}] (Lʹ = [MeC(NDIPP)CHC(Me)(NCH2CH2N(iPr)2)]−; 3: R = Me; 4: R = Ph) were studied. Reactions of these rare‐earth metal alkylidene complexes with PhCN give four kinds of products, depending on the rare‐earth metal ions, ancillary ligands and alkylidene groups of the complexes. In the reactions with tBuNC, unusual C‒P cleavage of alkylidene group and C‒C triple bond formation occur. Complexes 10 and 11 also react with PhSiH3 to provide the hydrides, which subsequently undergo Ln‐H addition to the C=N bond of the ancillary ligand L. DFT calculations were used to analyze the bonding in complex 10, that exhibits a polarized three centers Sm‒C‒P π interaction, and to rationalize the reactivity by computing reaction mechanisms. The difference of reactivity of PhCN and tBuNC is due to the electron density delocalization allowed by the phenyl group rather than the tBu group.

    更新日期:2018-07-18
  • Designing Explosive Poly(ionic liquid)s as Novel Energetic Polymers
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Binshen Wang; Yongan Feng; Xiujuan Qi; Mucong Deng; Junjun Tian; Qinghua Zhang

    The development of ionic liquids‐derived functional materials would be vital for stimulation of the interdisciplinary research in the fields of ionic liquids chemistry and material science. Here, a series of novel poly(ionic liquid)s with explosive capability are designed and prepared by introducing energetic nitrato group and nitro‐rich anions, such as nitrate, dinitramide, and nitroform into the polymeric chains. The as‐synthesized explosive poly(ionic liquid)s (E‐PILs) are fully characterized, and their physicochemical and detonation properties are investigated. All E‐PILs show higher detonation performances than state‐of‐the‐art energetic polymers including glycidyl azide polymer (GAP) and poly(glycidyl nitrate) [poly(GLYN)]. Some E‐PILs exhibit higher calculated detonation velocities and pressures than 2,4,6‐trinitrotoluene (TNT). These E‐PILs are promising candidates for applications as new high‐performance energetic polymers.

    更新日期:2018-07-18
  • Molecular Tweezers with Additional Recognition Sites
    Chem. Eur. J. (IF 5.16) Pub Date : 17 July 20
    Christian Heid; Andrea Sowislok; Torsten Schaller; Felix Niemeyer; Frank‐Gerrit Klärner; Thomas Schrader
    更新日期:2018-07-18
  • Photoinduced in Vivo Magnetic Resonance Imaging (MRI) with Rapid CO Release from an MnCO‐Protein Needle Composite
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-06-15
    Fuminori Hyodo; Takeya Sho; Basudev Maity; Kenta Fujita; Yoko Tachibana; Satoko Akashi; Megumi Mano; Yuki Hishikawa; Masayuki Matsuo; Takafumi Ueno
    更新日期:2018-07-18
  • Quantum‐effect on Bimetallic‐MOF for Construction of Two‐dimensional Co3O4‐embedded Nitrogen‐doped Porous Carbon Nanosheet‐arrays as Bifunctional Oxygen Electrocatalyst
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Hao Zhang; Jiaying Xu; Yiwen Jin; YinLin Tong; Qingyi Lu; Feng Gao

    Two‐dimensional (2D) materials refer to a class of materials with high electrical conductivity along 2D conducting channels and possessing abundant active sites in the form of surface atoms and edge sites, representing promising candidates for high‐performance fuel cells and water splitting electrocatalysts. Herein, we report an ammonia‐modulating method for the synthesis of nanosized bimetallic ZnCo‐ZIF, and owing to quantum effect the nanosized ZnCo‐ZIF can be transformed into a novel two‐dimensional nanosheet‐arrays as bi‐functional electrocatalysts. With ammonia amount increasing the size of ZnCo‐ZIF crystals can be controlled to less than 10 nm. The products from the nanosized particles through calcination have a distinct structure from the product of microsized nanoparticles due to quantum effect and appear to be well‐aligned two‐dimensional mono‐crystalline Co3O4‐embedded nitrogen‐doped porous carbon nanosheet‐arrays (2D‐MCo3O4‐NCNAs). These novel two‐dimensional nanosheet‐arrays lead to large active surface area, enhanced mass/charge transport capability, numerous active sites and strong structure stability. When used as bi‐functional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), the 2D‐MCo3O4‐NCNAs exhibit superior ORR activity as well as efficient OER activity in alkaline electrolyte, in comparison to the state‐of‐the‐art precious metal catalysts.

    更新日期:2018-07-18
  • Hydrogen‐Bonded Donor‐Acceptor Arrays at the Solution‐Graphite Interface
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Gangamallaiah Velpula; Mengmeng Li; Yunbin Hu; Yulian Zagranyarski; Wojciech Pisula; Klaus Müllen; Kunal Mali; Steven De Feyter

    Controlling the nanoscale morphology of organic thin films represents a critical challenge in the fabrication of organic (opto)electronic devices. The morphology of the (multicomponent) thin films in turn depends on the mutual orientation of the molecular components and their supramolecular packing on the surface. Here we show how the surface co‐assembly of electron‐donating and ‐accepting building blocks can be controlled via (supra)molecular design. Hexa‐peri‐hexabenzocoronene (HBC) derivatives with multiple hydrogen‐bonding (H‐bonding) sites were synthesized and their co‐assembly with alkyl‐substituted perylenetetracarboxy diimide (PDI) was studied using scanning tunneling microscopy (STM) at the solution‐graphite interface. STM data shows that electron rich HBCs co‐assemble laterally with electron deficient PDIs via pre‐programmed H‐bonding sites with high fidelity. The surface stoichiometry of the two components could be readily tuned by changing the number of H‐bonding sites on the HBC derivatives via organic synthesis. This model study highlights the utility of (supra)molecular design in co‐assembly of building blocks relevant for organic electronics.

    更新日期:2018-07-18
  • Thermodynamic Programming of Erbium(III) Coordination Complexes for Dual Visible‐Near Infrared Luminescence
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Claude Piguet; Bahman Golesorkhi; Laure Guénée; Homayoun Nozary; Alexandre Fürstenberg; Yan Suffren; Svetlana Eliseeva; Stéphane Petoud; Andreas Hauser

    Intrigued by the unexpected room‐temperature dual visible‐NIR luminescence observed for fast‐relaxing erbium complexes embedded in triple‐stranded helicates, this contribution explores a series of six tridentate N‐donor receptors L4‐L9 with variable aromaticities and alkyl substituents for extricating the stereo‐electronic requirements responsible for such scarce optical signatures. Detailed solid state (X‐ray diffraction, differential scanning calorimetry, optical spectroscopy) and solution (speciations and thermodynamic stabilities, spectrophotometry, NMR and optical spectroscopy) studies of mononuclear unsaturated [Er(Lk)2]3+ and saturated triple‐helical [Er(Lk)3]3+ model complexes reveal that the stereo‐electronic changes induced by the organic ligands affect inter‐ and intra‐molecular interactions to such an extent that (i) melting temperatures in solids, (ii) the affinity for trivalent erbium in solution, and (iii) optical properties in luminescent complexes can be rationally varied and controlled. With this toolkit in hand, mononuclear erbium complexes with low stabilities displaying only near‐infrared (NIR) emission can be transformed into molecular‐based dual Er‐centered visible/NIR emitters operating at room temperature in solids and in solutions.

    更新日期:2018-07-18
  • Metal‐Organic Layers Catalyze Photoreactions without Pore Size and Diffusion Limitations
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Ruoyu Xu; Tasha Drake; Guangxu Lan; Wenbin Lin

    Metal‐organic‐frameworks (MOFs) have emerged as promising single‐site solid catalysts for organic reactions. However, MOF catalysts suffer from pore size limitation and slow diffusion, which become more detrimental for photoreactions. Metal‐organic layers (MOLs) have unique ultrathin 2‐D monolayer structures and overcome pore size and diffusion limitations. Here we report the synthesis of photoactive Zr‐RuBPY MOL based on Zr‐oxo clusters and [Ru(bpy)3]2+‐containing linkers and its application in photocatalytic intramolecular and cross [2+2] cyclizations of enones as well as Meerwein addition reactions between aryl diazonium salts, styrenes, and nitriles. In contrast, the corresponding MOF catalyst failed in these photoreactions, due to either pore size limitation or restricted diffusion of reactive intermediates.

    更新日期:2018-07-18
  • Pressure‐induced Spin‐CrossOver features at variable temperature revealed by in situ Synchrotron Powder X‐Ray Diffraction
    Chem. Eur. J. (IF 5.16) Pub Date : 2018-07-17
    Philippe Guionneau; Elodie Tailleur; Mathieu Marchivie; Jean-Paul Itié; Patrick Rosa; Nathalie Daro

    An accurate high‐pressure X‐ray diffraction investigation at various temperatures on powder of a spin‐crossover (SCO) complex has allowed the rare deconvolution of the structural features of the high‐spin and low‐spin phases. As a result, the pressure dependence of the structural parameters of the high‐spin and low‐spin phases can be discussed independently in the pressure domain where both phases co‐exist within the powder. Consequently, crucial unprecedented information are given such as the variation of bulk moduli with temperature, similar here in amplitude for both spin phases, the temperature‐dependence of the pressure‐induced SCO abruptness, the temperature dependence of the pressure at which SCO occurs and arguments for a possible piezo‐hysteresis. Performed on the molecular complex [Fe(PM PeA)2(NCSe)2], this study reveals a pressure‐induced SCO at 0.16 GPa and demonstrates that, when increasing temperature, the pressure of transition increases linearly, the abruptness of the pressure‐induced SCO strongly increases and the bulk moduli decrease.

    更新日期:2018-07-18
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
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