Chemistry - A European Journal

Cover image for Vol. 20 Issue 14

April 1, 2014

Volume 20, Issue 14

Pages 3853–4169

  1. Cover Pictures

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
    1. You have free access to this content
      Cover Picture: Heteronuclear NMR Spectroscopy as a Surface-Selective Technique: A Unique Look at the Hydroxyl Groups of γ-Alumina. (Chem. Eur. J. 14/2014) (page 3853)

      Dr. Mostafa Taoufik, Dr. Kai C. Szeto, Dr. Nicolas Merle, Dr. Iker Del Rosal, Dr. Laurent Maron, Dr. Julien Trébosc, Dr. Grégory Tricot, Dr. Régis M. Gauvin and Dr. Laurent Delevoye

      Version of Record online: 27 MAR 2014 | DOI: 10.1002/chem.201490054

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      The combination of high magnetic field and advanced 1H–27Al correlation solid-state NMR techniques provides unprecedented data on the topology of the surface hydroxyl groups of γ-alumina. For more details, see the Full Paper by R. M. Gauvin, L. Maron, M. Taoufik et al. on page 4038 ff. Photograph: Rock Islands, Palau, copyright: optionm – fotolia. com. We thank Matthieu Morin for his assistance with artwork.

    2. You have free access to this content
      Back Cover: Influence of Substituents and Functional Groups on the Surface Composition of Ionic Liquids (Chem. Eur. J. 14/2014) (page 4172)

      Dr. Claudia Kolbeck, Inga Niedermaier, Dr. Alexey Deyko, Dr. Kevin R. J. Lovelock, Dr. Nicola Taccardi, Wei Wei, Prof. Dr. Peter Wasserscheid, Dr. Florian Maier and Prof. Dr. Hans-Peter Steinrück

      Version of Record online: 27 MAR 2014 | DOI: 10.1002/chem.201490057

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      Surface enrichment of ionic liquids with a large variety of functional groups is studied by angle-resolved X-ray photoelectron spectroscopy. In their Full Paper on page 3954 ff., H.-P. Steinrück et al. show that the molecular orientation of the ions at the surface strongly depends on the inter- and intramolecular interactions of the ionic head groups and their substituents.

  2. Cover Profile

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
    1. You have free access to this content
      Heteronuclear NMR Spectroscopy as Surface-Selective Technique: A Unique Look at the Hydroxyl Groups of γ-Alumina (page 3856)

      Dr. Mostafa Taoufik, Dr. Kai C. Szeto, Dr. Nicolas Merle, Dr. Iker Del Rosal, Dr. Laurent Maron, Dr. Julien Trébosc, Dr. Grégory Tricot, Dr. Régis M. Gauvin and Dr. Laurent Delevoye

      Version of Record online: 13 MAR 2014 | DOI: 10.1002/chem.201400425

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      Alumina is a material involved in strategic industrial catalytic processes.” Read more about the story behind the cover in the Cover Profile and about the research itself on page 4038 ff. (DOI: 10.1002/chem.201304883).

  3. Graphical Abstract

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
  4. News

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
  5. Minireview

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
    1. Dual Catalysis

      Dual Catalysis Sees the Light: Combining Photoredox with Organo-, Acid, and Transition-Metal Catalysis (pages 3874–3886)

      Dr. Matthew N. Hopkinson, Basudev Sahoo, Dr. Jun-Long Li and Prof. Dr. Frank Glorius

      Version of Record online: 5 MAR 2014 | DOI: 10.1002/chem.201304823

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      De(light)ful catalysis! The merger of photoredox catalysis with another catalytic mode can result in novel, visible-light-promoted reactions that do not proceed by using either catalyst independently. Herein, the different ways that two catalytic modes can operate in tandem are highlighted, focusing on dual-catalyzed organic processes that merge photoredox with organo-, acid, and transition-metal catalysis.

  6. Communications

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
    1. Hydrogels

      Templating the Self-Assembly of Pristine Carbon Nanostructures in Water (pages 3888–3893)

      Dr. Miriam Mba, Dr. Ana I. Jiménez and Dr. Alessandro Moretto

      Version of Record online: 18 MAR 2014 | DOI: 10.1002/chem.201304912

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      Research on carbon nanostructures faces two challenges: First their low solubility in water and second, the need for ordered architectures at the nanoscale level. It is shown that a novel amino acid based low-molecular-weight gelator (see figure) can be used to effectively disperse pristine carbon nanostructures in water and to drive their ordered self-assembly into supramolecular hydrogels by a noncovalent mechanochemical approach.

    2. Polyoxometalates

      Regioselective Hydrolysis of Human Serum Albumin by ZrIV-Substituted Polyoxotungstates at the Interface of Positively Charged Protein Surface Patches and Negatively Charged Amino Acid Residues (pages 3894–3897)

      Karen Stroobants, Dr. Gregory Absillis, Dr. Eva Moelants, Prof. Dr. Paul Proost and Prof. Dr. Tatjana N. Parac-Vogt

      Version of Record online: 5 MAR 2014 | DOI: 10.1002/chem.201303622

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      Polyoxometalates for protein hydrolysis: Complexes comprising the Lewis acidic ZrIV metal and protein binding polyoxotungstate ligands of Lindqvist-, Keggin- and Wells–Dawson-type were found to region selectively hydrolyze human serum albumin at four distinct positions (see illustration). Higher reactivities were found for structures with higher polyoxometalate charges and the cleavage positions were found in protein regions of mixed charge.

    3. Supramolecular Catalysis

      Dinuclear Ru–Aqua Complexes for Selective Epoxidation Catalysis Based on Supramolecular Substrate Orientation Effects (pages 3898–3902)

      Dr. Carlo Di Giovanni, Dr. Albert Poater, Dr. Jordi Benet-Buchholz, Prof. Luigi Cavallo, Prof. Miquel Solà and Prof. Antoni Llobet

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201304699

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      A new Ru–aqua complex that behaves as a powerful epoxidation catalyst for a wide range of linear and cyclic alkenes is reported. High turnover numbers and frequencies are obtained by using PhIO as oxidant. The complex shows an outstanding stereospecificity for both cis and trans olefins towards the formation of their corresponding cis and trans epoxides (see figure).

    4. Gold Catalysis

      Inorganic–Organic Heteropolyacid–Gold(I) Hybrids: Structures and Catalytic Applications (pages 3903–3907)

      Damien Hueber, Marie Hoffmann, Dr. Benoît Louis, Prof. Dr. Patrick Pale and Dr. Aurélien Blanc

      Version of Record online: 26 FEB 2014 | DOI: 10.1002/chem.201304680

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      Gold(I)-polyoxometalate hybrid complexes ([AuPPh3MeCN]xH4−xSiW12O40, x=1–4) were synthesized and characterized. [AuPPh3MeCN]H3SiW12O40 exhibited better catalytic activity and selectivity compared with standard, homogeneous, gold catalysts in the new rearrangement of propargylic gem-diesters (see scheme).

    5. Amidocuprates

      You have full text access to this OnlineOpen article
      Structural Effects in Lithiocuprate Chemistry: The Elucidation of Reactive Pentametallic Complexes (pages 3908–3912)

      Philip J. Harford, Andrew J. Peel, Joseph P. Taylor, Dr. Shinsuke Komagawa, Prof. Paul R. Raithby, Thomas P. Robinson, Prof. Dr. Masanobu Uchiyama and Dr. Andrew E. H. Wheatley

      Version of Record online: 19 FEB 2014 | DOI: 10.1002/chem.201304824

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      Cu on the other side: A series of new amidocuprates were studied. X-ray crystallography of amidocuprates prepared using copper(I) halides and 2,2,6,6-tetramethylpiperidine revealed Lipshutz-type dimers (see graphic). cis-2,6-Dimethylpiperidine gave a remarkable adduct motif: triangulated, pentametallic amidocuprates based on a lithium halide core. These adducts suggest a new mechanism for forming reactive monomeric Gilman-type cuprate bases.

    6. Phosphorous Heterocycles

      New P[BOND]N Cage Compounds Generated by Small-Molecule Activation (pages 3913–3916)

      Alexander Hinz, Prof. Dr. Axel Schulz and Dr. Alexander Villinger

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201400143

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      Trapped in a cage: New small Group 15 cage molecules were obtained by reactions of diphosphadiazanediyls with dipnictenes. These species were characterized spectroscopically, structurally, and computationally (see figure).

    7. Multicatalysis

      You have full text access to this OnlineOpen article
      Merging Gold and Organocatalysis: A Facile Asymmetric Synthesis of Annulated Pyrroles (pages 3917–3921)

      Daniel Hack, Dr. Charles C. J. Loh, Jan M. Hartmann, Prof. Dr. Gerhard Raabe and Prof. Dr. Dieter Enders

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201400407

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      Outwitted: The combination of cinchona-alkaloid-derived primary amine and AuI–phosphine catalysts allowed the selective C[BOND]H functionalization of two adjacent carbon atoms of pyrroles under mild reaction conditions. This sequential dual activation provides seven-membered-ring-annulated pyrrole derivatives in excellent yields and enantioselectivities (see scheme).

    8. Nanoparticles

      Vortex-Pattern Self-Assembly in Mn-Doped ZnSe Nanorods (pages 3922–3926)

      Shinjita Acharya, Suresh Sarkar, Supriya Chakraborty and Dr. Narayan Pradhan

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201304724

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      Evaporation-mediated self-assembly of nanorods can generate intriguing patterns on solid substrates, among which vortex patterns are especially interesting (see figure). With light-emitting, Mn-doped ZnSe nanorods, both pillar-like and vortex self-assembled patterns were achieved on TEM grids. The method can be explored for applications of self-assembled nanorods with visible emission in a Cd-free system.

    9. Synthetic Methods

      Highly Diastereoselective and Regioselective Copper-Catalyzed Nitrosoformate Dearomatization Reaction under Aerobic-Oxidation Conditions (pages 3927–3931)

      Weibo Yang, Long Huang, Yang Yu, Daniel Pflästerer, Dr. Frank Rominger and Prof. Dr. A. Stephen K. Hashmi

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201400321

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      Cu does it! An unprecedented copper-catalyzed nitrosoformate dearomatization reaction under aerobic oxidation has been developed. This discovery expands the traditional nitrosoformate ene reaction and nitrosoformate Diels–Alder reaction to a new type of transformation. Intermolecular and intra-/intermolecular reaction modes demonstrate an entirely different N- or O-nitrosoformate selectivity (see scheme; OTf=trifluoromethanesulfonyl, Ts=p-toluenesulfonyl).

    10. Heterocycles

      Synthesis of Indazoles and Azaindazoles by Intramolecular Aerobic Oxidative C[BOND]N Coupling under Transition-Metal-Free Conditions (pages 3932–3938)

      Jiantao Hu, Huacheng Xu, Pengju Nie, Xiaobo Xie, Prof. Dr. Zongxiu Nie and Prof. Dr. Yu Rao

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201304923

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      A transition-metal-free oxidative C[BOND]N coupling method has been developed for the synthesis of 1H-azaindazoles and 1H-indazoles from easily accessible hydrazones (see scheme). The procedure uses TEMPO, a basic additive, and dioxygen gas as the terminal oxidant. This reaction demonstrates better reactivity, functional group tolerance, and broader scope than comparable metal catalyzed reactions. TEMPO=2,2,6,6-tetramethyl-1-piperidinyloxy.

  7. Full Papers

    1. Top of page
    2. Cover Pictures
    3. Cover Profile
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Communications
    8. Full Papers
    1. Fluorescence

      Synthetic Control of Spectroscopic and Photophysical Properties of Triarylborane Derivatives Having Peripheral Electron-Donating Groups (pages 3940–3953)

      Dr. Akitaka Ito, Kazuyoshi Kawanishi, Dr. Eri Sakuda and Prof. Dr. Noboru Kitamura

      Version of Record online: 18 MAR 2014 | DOI: 10.1002/chem.201304207

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      Tunable fluorescence: The spectroscopic and photophysical properties of triarylborane derivatives can be controlled by the nature of the triarylborane core and peripheral electron-donating groups. The fluorescence color was tunable from blue to red owing to charge-transfer (CT) interactions between the triarylborane core and the peripheral electron-donating groups (see figure).

    2. Ionic Liquids

      Influence of Substituents and Functional Groups on the Surface Composition of Ionic Liquids (pages 3954–3965)

      Dr. Claudia Kolbeck, Inga Niedermaier, Dr. Alexey Deyko, Dr. Kevin R. J. Lovelock, Dr. Nicola Taccardi, Wei Wei, Prof. Dr. Peter Wasserscheid, Dr. Florian Maier and Prof. Dr. Hans-Peter Steinrück

      Version of Record online: 18 MAR 2014 | DOI: 10.1002/chem.201304549

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      Scratching the surface: The surface behavior of various functionalized ionic liquids (ILs) is studied by angle-resolved X-ray photoelectron spectroscopy and conclusions on surface-enrichment effects and molecular orientation of cations and anions are derived (see figure; Im=imidazolium, Tf=trifluoromethanesulfonyl). Overall, surface enrichment is only observed for functional groups that interact weakly with the ionic head groups.

    3. Host–Guest Systems

      Origins of Large Rate Enhancements in the Nazarov Cyclization Catalyzed by Supramolecular Encapsulation (pages 3966–3973)

      Dr. Courtney J. Hastings, Prof. Robert G. Bergman and Prof. Kenneth N. Raymond

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201303885

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      A self-assembled supramolecular host catalyzes the Nazarov cyclization of 1,3-pentadienols under mild, aqueous conditions. The catalyzed reaction rate is enhanced by a factor of over 106 compared with the background reaction rate, one of the largest reported for supramolecular catalysis. Analysis of the reaction-energy profile revealed that transition-state stabilization contributes significantly to the dramatically enhanced reaction rate (see scheme).

    4. Density Functional Calculations

      Understanding Stability Trends along the Lanthanide Series (pages 3974–3981)

      Dr. Martín Regueiro-Figueroa, Dr. David Esteban-Gómez, Dr. Andrés de Blas, Dr. Teresa Rodríguez-Blas and Dr. Carlos Platas-Iglesias

      Version of Record online: 27 FEB 2014 | DOI: 10.1002/chem.201304469

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      Predictive math: A computational approach based on DFT calculations was developed to rationalize and predict the stability trends of Ln3+ complexes in aqueous solution (see figure), an issue of critical importance for the design of more efficient ligands for Ln3+ discrimination.

    5. Electrochromic Materials

      Novel Bipyridinium Ionic Liquids as Liquid Electrochromic Devices (pages 3982–3988)

      Noémi Jordão, Dr. Luis Cabrita, Prof. Dr. Fernando Pina and Dr. Luís C. Branco

      Version of Record online: 27 FEB 2014 | DOI: 10.1002/chem.201304451

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      Novel mono and dialkylbipyridinium cations combined with halides and bis(trifluoromethanesulfonyl)imide anions were prepared and characterized. Thermal, rheological, and electrochemical properties were studied for different bipyridinium salts. Reversible liquid electrochromic devices composed of dialkylbipyridinium-NTf2 ionic liquids (see figure; IL=ionic liquid) have been successfully developed.

    6. Carbene Chemistry

      Cyclodimerization versus Polymerization of Methyl Methacrylate Induced by N-Heterocyclic Carbenes: A Combined Experimental and Theoretical Study (pages 3989–3997)

      Winnie Nzahou Ottou, Damien Bourichon, Dr. Joan Vignolle, Anne-Laure Wirotius, Dr. Fredéric Robert, Prof. Yannick Landais, Dr. Jean-Marc Sotiropoulos, Dr. Karinne Miqueu and Prof. Daniel Taton

      Version of Record online: 6 MAR 2014 | DOI: 10.1002/chem.201304492

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      Cyclodimerizing MMA! NHCiPr (NHC=N-heterocyclic carbene) unexpectedly reacts with methyl methacrylate (MMA) by forming a stable imidazolium–enolate cyclodimer (NHCiPr/MMA=1:2), in contrast to polymerization, which is induced by NHCtBu (see scheme). DFT calculations on both mechanistic pathways highlight the differences observed between these two very similar NHCs.

    7. Oxidative Coupling

      C,C- and N,C-Coupled Dimers of 2-Aminotetraphenylporphyrins: Regiocontrolled Synthesis, Spectroscopic Properties, and Quantum-Chemical Calculations (pages 3998–4006)

      Dr. Torsten Bruhn, Dipl.-Chem. Franziska Witterauf, Dr. Daniel C. G. Götz, Carina T. Grimmer, Dipl.-Chem. Max Würtemberger, Prof. Dr. Udo Radius and Prof. Dr. Gerhard Bringmann

      Version of Record online: 26 FEB 2014 | DOI: 10.1002/chem.201304169

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      All in the spin: Depending on the oxidative coupling conditions (Ag or Fe vs. Cu), aminoporphyrin monomers can be selectively dimerized to give axially chiral C,C-coupled β,β-diaminobisporphyrins or an N,C-coupled pyrazin-fused dimer (see figure). DFT calculations suggest that the oxidant in combination with the solvent has a strong impact on the spin density of the intermediate radical cation and, consequently, on the regioselectivity of the reaction.

    8. Macrocyclic Peptides

      Synthesis and Conformational Analysis of Cyclic Homooligomers from Pyranoid ε-Sugar Amino Acids (pages 4007–4022)

      Dr. Andrés Feher-Voelger, Jorge Borges-González, Dr. Romen Carrillo, Dr. Ezequiel Q. Morales, Dr. Javier González-Platas and Dr. Tomás Martín

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201303841

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      To fold or not to fold: ε-Sugar amino acids (ε-SAAs) have proven to be privileged scaffolds for the synthesis of conformationally modulated cyclic peptides. An appendix on the sugar moiety helps to modulate the conformation equilibrium between the folded and unfolded structures by modification of the internal network of noncovalent interactions (see figure).

    9. Supramolecular Polymers

      Synthesis of Doubly Ethyl-Bridged Bis(p-sulfonatocalix[4]arene) and Its Supramolecular Polymerization with Viologen Dimer (pages 4023–4031)

      Kun-Peng Wang, Dr. Dong-Sheng Guo, Dr. Hong-Xia Zhao and Prof. Yu Liu

      Version of Record online: 26 FEB 2014 | DOI: 10.1002/chem.201303344

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      Calixarene polymerization: A novel doubly ethyl-bridged bis(p-sulfonatocalix[4]arene) (d-SC4A) has been prepared with improved molecular conformation and rigidity for supramolecular polymerization. A highly soluble, linear polymer has been constructed by the complexation of d-SC4A with viologen dimer in water (see figure). The obtained polymer exhibits high solubility as well as a high degree of polymerization and viscosity. The assembly/disassembly can be operated by electrostimulus.

    10. Sensors

      Iron(III)-Quantity-Dependent Aggregation–Dispersion Conversion of Functionalized Gold Nanoparticles (pages 4032–4037)

      Linyi Bai, Dr. Liangliang Zhu, Chung Yen Ang, Dr. Xin Li, Shaojue Wu, Dr. Yongfei Zeng, Prof. Hans Ågren and Prof. Yanli Zhao

      Version of Record online: 5 MAR 2014 | DOI: 10.1002/chem.201303958

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      Iron works: 4-Piperazinyl-1,8-naphthalimide-functionalized gold nanoparticles (AuNPs) for quantitative recognition of FeIII ions with dual signal output were realized by taking advantage of FeIII-quantity-controlled chelation-mode transformations of the piperazinyl moiety on AuNPs to result in an aggregation–dispersion conversion of AuNPs in solution (see figure).

    11. Surface Chemistry

      Heteronuclear NMR Spectroscopy as a Surface-Selective Technique: A Unique Look at the Hydroxyl Groups of γ-Alumina. (pages 4038–4046)

      Dr. Mostafa Taoufik, Dr. Kai C. Szeto, Dr. Nicolas Merle, Dr. Iker Del Rosal, Dr. Laurent Maron, Dr. Julien Trébosc, Dr. Grégory Tricot, Dr. Régis M. Gauvin and Dr. Laurent Delevoye

      Version of Record online: 6 MAR 2014 | DOI: 10.1002/chem.201304883

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      Illuminating alumina: Thanks to the combination of high magnetic field and advanced (heteronuclear) correlation techniques, solid-state NMR provides unprecedented insights on the topology of the surface hydroxyl groups of γ-alumina (see figure; HMQC=heteronuclear multiple-quantum correlation).

    12. Click Chemistry

      A Highly Active and Magnetically Recoverable Tris(triazolyl)–CuI Catalyst for Alkyne–Azide Cycloaddition Reactions (pages 4047–4054)

      Dr. Dong Wang, Laetitia Etienne, María Echeverria, Prof. Sergio Moya and Prof. Dr. Didier Astruc

      Version of Record online: 26 FEB 2014 | DOI: 10.1002/chem.201304536

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      Magnets make it easy: Magnetically recoverable tris(triazolyl)–CuI catalysts have been synthesized for the preparation of 1,2,3-triazoles (see figure). These catalysts display high activity, easy recoverability, and efficient reusability. Reactions are performed under aqueous reaction conditions and a broad substrate scope is demonstrated. These catalysts can also be applied to a one-pot synthesis of triazoles by means of a cascade reaction.

    13. Lithium-Ion Batteries

      Facile Mechanochemical Synthesis of Nano SnO2/Graphene Composite from Coarse Metallic Sn and Graphite Oxide: An Outstanding Anode Material for Lithium-Ion Batteries (pages 4055–4063)

      Fei Ye, Bote Zhao, Prof. Ran Ran and Prof. Zongping Shao

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201304720

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      A facile ball-milling method for large-scale synthesis of a SnO2 nanocrystal/graphene composite by using coarse metallic Sn particles and cheap graphite oxide (GO) as raw materials is demonstrated. By using the SnO2 nanocrystals/graphene composite as an anode material for lithium-ion batteries, a high specific capacity of 891 mA h g−1 was achieved even after 50 cycles at 100 mA g−1 (see figure).

    14. Spin Trapping

      Synthesis and Spin-Trapping Properties of a Trifluoromethyl Analogue of DMPO: 5-Methyl-5-trifluoromethyl-1-pyrroline N-Oxide (5-TFDMPO) (pages 4064–4071)

      Dr. Hakim Karoui, Dr. Céline Nsanzumuhire, Dr. François Le Moigne, Dr. Micael Hardy, Prof. Didier Siri, Dr. Etienne Derat, Prof. Antal Rockenbauer, Dr. Olivier Ouari and Prof. Paul Tordo

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201303774

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      New pieces to the puzzle! A new fluorinated 5,5-dimethyl-1-pyrroline N-oxide (DMPO)-based spin trap (5-TFDMPO; see figure) was synthesized and studied by EPR/spin-trapping techniques. The properties of the new spin trap are reported for various radicals. The role of the trifluoromethyl group on the spin-trapping properties of the superoxide radical is discussed on the basis of a comparison with other spin traps.

    15. Electrochemistry

      The Significant Role of Carboxylated Carbonaceous Fragments in the Electrochemistry of Carbon Nanotubes (pages 4072–4076)

      Xiao Ma, Li Jia, Lu Zhang and Prof. Liande Zhu

      Version of Record online: 24 FEB 2014 | DOI: 10.1002/chem.201304311

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      Carbonaceous fragments: Purification or pre-treatment of carbon nanotubes (CNTs) with nitric acid gives rise to enormous carboxylated carbonaceous fragments that are irreversibly adsorbed on the surfaces of carbon nanotubes. The adsorption of the fragments significantly boosts the electrocatalytic behaviour of the carbon nanotubes (see figure). This finding could be particularly meaningful to uncover the mysterious electrocatalysis of carbon nanotubes.

    16. C[BOND]C Bond Cleavage

      Comparative Studies of Thermally Induced Homolytic Carbon[BOND]Carbon Bond Cleavage Reactions of Strained Dicarba[2]ferrocenophanes and Their Ring-Opened Oligomers and Polymers (pages 4077–4085)

      Andrew D. Russell, Prof. Joe B. Gilroy and Prof. Ian Manners

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201304396

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      Getting ROPed in: Studies of the mechanistic processes that occur under the conditions of thermal ring-opening polymerization (ROP) of dicarba[2]ferrocenophanes have revealed a homolytic C[BOND]C bond cleavage pathway that also proceeds in the absence of ring-strain (see scheme).

    17. Configurational Stability

      On the Configurational Stability of Chiral, Nonracemic Fluoro- and Iodo-[D1]Methyllithiums (pages 4086–4091)

      Dr. Dagmar C. Kail, Petra Malova Krizkova, Dr. Anna Wieczorek and Dr. Friedrich Hammerschmidt

      Version of Record online: 27 FEB 2014 | DOI: 10.1002/chem.201304766

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      The microscopic configurational stability of enantiomerically pure fluoro-[D1]methyllithiums prepared by tin–lithium exchange in the presence of excess benzaldehyde or acetophenone has been investigated. Depending on the reaction temperature, a portion of the generated fluoro-[D1]methyllithiums was added to the electrophiles to give fluorohydrins; the remaining portions disintegrated to carbene and LiF (see scheme).

    18. Organic Chemistry

      ortho-Benzoxylation of N-Alkyl Benzamides with Aromatic Acids Catalyzed by Ruthenium(II) Complex (pages 4092–4097)

      Kishor Padala and Dr. Masilamani Jeganmohan

      Version of Record online: 26 FEB 2014 | DOI: 10.1002/chem.201304646

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      C[BOND]H bond activation: A highly regioselective ortho-benzoxylation of benzamides with substituted benzoic acids in the presence of a ruthenium catalyst is described. Further, Ru-catalyzed alkenylation is carried out at the ortho C[BOND]H bond of benzoxylated N-alkyl benzamides with alkenes in water solvent. Subsequently, the benzoxyl moiety of N-alkyl benzamides was converted into the hydroxyl group in the presence of base or acid (see scheme).

    19. Proton-Coupled Electron Transfer

      Distance Dependence of Bidirectional Concerted Proton–Electron Transfer in Phenol-Ru(2,2′-bipyridine)32+ Dyads (pages 4098–4104)

      Dr. Jing Chen, Martin Kuss-Petermann and Prof. Dr. Oliver S. Wenger

      Version of Record online: 26 FEB 2014 | DOI: 10.1002/chem.201304256

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      Time for a concert! The dependence of the rates for bidirectional concerted proton–electron transfer (CPET) on the electron donor/electron acceptor distance was determined for the first time (see scheme). The results are relevant in the context of photodriven separation of protons and electrons across natural or artificial membranes as a means of light-to-chemical energy conversion.

    20. Organic Synthesis

      Nickel-Catalyzed Synthesis of N-Aryl-1,2-dihydropyridines by [2+2+2] Cycloaddition of Imines with Alkynes through T-Shaped 14-Electron Aza-Nickelacycle Key Intermediates (pages 4105–4110)

      Dr. Yoichi Hoshimoto, Tomoya Ohata, Dr. Masato Ohashi and Prof. Dr. Sensuke Ogoshi

      Version of Record online: 27 FEB 2014 | DOI: 10.1002/chem.201304830

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      Oxidative cyclization: The title reaction has been achieved for the first time by employing nickel(0)/N-heterocyclic carbene (NHC) catalyst. In addition, isolation of a T-shaped 14-electron aza-nickelacycle, which would be a key reaction intermediate, is also reported (see scheme).

    21. Surface Reactivity

      A Single-Molecule-Level Mechanistic Study of Pd-Catalyzed and Cu-Catalyzed Homocoupling of Aryl Bromide on an Au(111) Surface (pages 4111–4116)

      Dr. Jinne Adisoejoso, Tao Lin, Xue Song Shang, Ke Ji Shi, Aditi Gupta, Prof. Dr. Pei Nian Liu and Prof. Dr. Nian Lin

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201304443

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      Engaged on the surface: On-surface Pd- and Cu-catalyzed C[BOND]C coupling reactions between phenyl bromide-functionalized porphyrin derivatives were achieved under ultra-high vacuum conditions, and the kinetics of the reaction were investigated by using scanning tunneling microscopy and kinetic Monte Carlo simulations. Comparison of the two catalysts revealed distinctive reaction kinetics (see figure).

    22. Supramolecular Chemistry

      Solvent-Dependent Self-Assembly Behaviour and Speciation Control of Pd6L8 Metallo-supramolecular Cages (pages 4117–4125)

      James J. Henkelis, Dr. Julie Fisher, Dr. Stuart L. Warriner and Prof. Michaele J. Hardie

      Version of Record online: 3 MAR 2014 | DOI: 10.1002/chem.201304437

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      All sorted: Stella octangular [Pd6L8]12+ metallo-cages with chiral propylated cyclotriveratrylene-type ligands exhibit homochiral self-sorting in MeCN or MeNO2 but not in DMSO. Furthermore, differences in the favourability of the metallo-cage with propylated or methylated ligands can be used to control speciation in solution from heteroleptic to predominantly single homoleptic to dual homoleptic metallo-cages.

    23. Fluorescence

      Tunable Fluorophores Based on 2-(N-Arylimino)pyrrolyl Chelates of Diphenylboron: Synthesis, Structure, Photophysical Characterization, and Application in OLEDs (pages 4126–4140)

      Dr. D. Suresh, Patrícia S. Lopes, Bruno Ferreira, Cláudia A. Figueira, Dr. Clara S. B. Gomes, Dr. Pedro T. Gomes, Dr. Roberto E. Di Paolo, Prof. António L. Maçanita, Dr. M. Teresa Duarte, Dr. Ana Charas, Dr. Jorge Morgado and Prof. Maria José Calhorda

      Version of Record online: 13 MAR 2014 | DOI: 10.1002/chem.201303607

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      Fluorescent­ N,N′-boron chelate complexes: Mononuclear boron complexes of 2-(N-arylimino)pyrrolyl emit violet to bluish-green colors in solution (see figure, ITO=indium tin oxide, PEDOT:PSS=poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid)), depending on the substituents on the N-aryl group. Organic light-emitting diodes have been successfully fabricated with the new boron complexes, achieving luminances of the order of 3000 cd m−2.

    24. Hydrogen Generation

      On the Importance of Decarbonylation as a Side-Reaction in the Ruthenium-Catalysed Dehydrogenation of Alcohols: A Combined Experimental and Density Functional Study (pages 4141–4155)

      Dr. Nicolas Sieffert, Romain Réocreux, Patrizia Lorusso, Prof. Dr. David J. Cole-Hamilton and Prof. Dr. Michael Bühl

      Version of Record online: 5 MAR 2014 | DOI: 10.1002/chem.201303722

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      Competitive decarbonylation! A combination of DFT calculations and isotopic labelling experiments has shed light on the mechanism of the decarbonylation reaction that occurs as an important side-reaction during the ruthenium-catalyzed production of hydrogen from alcohols by dehydrogenation (see scheme). It is shown that multiple reaction pathways operate and that decarbonylation is competitive with dehydrogenation, at least for simple primary alcohols.

    25. Synthetic Methods

      Facile One-Pot Synthesis of [1, 2, 3]Triazolo[1, 5-a]Pyridines from 2-Acylpyridines by Copper(II)-Catalyzed Oxidative N[BOND]N Bond Formation (pages 4156–4162)

      Dr. Tasuku Hirayama, Dr. Satoshi Ueda, Takahiro Okada, Norihiko Tsurue, Prof. Kensuke Okuda and Prof. Hideko Nagasawa

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201302997

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      In the same pot: [1, 2, 3]Triazolo[1, 5-a]pyridines are synthesized from the corresponding 2-acylpyridines by a one-pot method, consisting of hydrazonation followed by oxidative cyclization through copper(II)-catalyzed N[BOND]N bond formation (see scheme).

    26. Methane Activation

      Methane Activation by Diatomic Molybdenum Carbide Cations (pages 4163–4169)

      Zi-Yu Li, Zhen Yuan, Dr. Yan-Xia Zhao and Prof. Dr. Sheng-Gui He

      Version of Record online: 25 FEB 2014 | DOI: 10.1002/chem.201304042

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      Methane activation and C[BOND]C coupling: Methane conversion to ethylene has been observed in its reaction with MoC+ (see scheme). Hydrogen atom transfer (HAT) from CH4 to C rather than to Mo initiates the reaction. Further C[BOND]C coupling and hydrogen transfers lead to the formation of C2H4. The bond strength preservation of Mo[BOND]C is important in methane activation.

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