Chemistry - A European Journal

Cover image for Vol. 18 Issue 15

April 10, 2012

Volume 18, Issue 15

Pages 4437–4795

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. You have free access to this content
      Cover Picture: Bonding in a Borylene Complex Investigated by Photoionization and Dissociative Photoionization (Chem. Eur. J. 15/2012) (page 4437)

      Dipl.-Chem. Kathrin H. Fischer, Dr. Michael Schneider, Prof. Dr. Ingo Fischer, Dipl.-Chem. Bernd Pfaffinger, Prof. Dr. Holger Braunschweig, Prof. Dr. Bálint Sztáray and Dr. Andras Bodi

      Version of Record online: 30 MAR 2012 | DOI: 10.1002/chem.201290055

      Thumbnail image of graphical abstract

      Synchrotron radiation and imaging photoelectron photoion coincidence spectroscopy were used to investigate chemical bonding in a borylene complex. The Cr–B bond stayed intact even at the highest photon energies after the sequential loss of all CO ligands, demonstrating its stability. Appearance energies and bond dissociation energies were determined by fitting a simplified statistical adiabatic channel model to the experimental fractional ion abundances and dissociation rates as a function of ion internal energy. For more details see the Full Paper by I. Fischer, A. Bodi et al. on page 4533 ff.

  2. Inside Cover

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. Inside Cover: On Oxygen-Containing Groups in Chemically Modified Graphenes (Chem. Eur. J. 15/2012) (page 4438)

      Dr. Alessandra Bonanni, Dr. Adriano Ambrosi and Prof. Martin Pumera

      Version of Record online: 30 MAR 2012 | DOI: 10.1002/chem.201290056

      Thumbnail image of graphical abstract

      Light is shed on the amount and type of oxygen-containing groups on graphene oxide mats. Four graphene materials were characterized by a wide variety of methods, such as high-resolution X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, UV/Vis spectroscopy, TEM, and voltammetry, to establish connections between the structures of these materials with different oxygen functionalities and the electrochemical behavior. For details, see the Full Paper by M. Pumera et al on page 4541 ff.

  3. Graphical Abstract

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
  4. News

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
  5. Concept

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. DNA

      DNA Architectonics: towards the Next Generation of Bio-inspired Materials (pages 4456–4469)

      Dr. Eugen Stulz

      Version of Record online: 8 MAR 2012 | DOI: 10.1002/chem.201102908

      Thumbnail image of graphical abstract

      Any which way but loose: DNA has become a fascinating construction material for nanosized objects (see figure); these are beginning to play an important role in nanotechnology due to their ability to form structures with function. This article highlights the recent developments in the field of DNA architectonics, including 2D and 3D structures, nanoparticle complexes, chemical modification and DNA-based nanodevices.

  6. Essay

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. Chemical Concepts

      Observations and Descriptions versus Explanations—An Example: Does Nature, Does Theory Know About Steric Hindrance? (pages 4470–4479)

      Prof. Dr. W. H. Eugen Schwarz and Prof. Dr. Hubert Schmidbaur

      Version of Record online: 8 MAR 2012 | DOI: 10.1002/chem.201102687

      Thumbnail image of graphical abstract

      Physical description—chemical explanation: Traditional chemical concepts such as steric hindrance or the various types of chemical bonding should not be rejected; they can indeed be underpinned by quantum chemical theory. Toward this aim more is needed, however, than the measurement and calculation of the precursors and products. Also the analysis of non-stationary intermediate states is required which disclose the internal relaxation mechanism of the geometric and electronic structures. Thereby, conceptual pitfalls are avoided.

  7. Communications

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. C[BOND]H Activation

      Diastereo- and Enantioselective Intramolecular C(sp3)[BOND]H Arylation for the Synthesis of Fused Cyclopentanes (pages 4480–4484)

      Dr. Nicolas Martin, Cathleen Pierre, Dr. Michaël Davi, Dr. Rodolphe Jazzar and Prof. Dr. Olivier Baudoin

      Version of Record online: 12 MAR 2012 | DOI: 10.1002/chem.201200018

      Thumbnail image of graphical abstract

      All C[BOND]H bonds are not equal: The intramolecular arylation of unactivated C(sp3)[BOND]H bonds in the presence of a chiral Pd/binepine catalyst allows the synthesis of fused cyclopentanes efficiently and in an diastereo- and enantioselective manner (see scheme).

      Corrected by:

      Corrigendum: Corrigendum: Diastereo- and Enantioselective Intramolecular C(sp3)[BOND]H Arylation for the Synthesis of Fused Cyclopentanes

      Vol. 20, Issue 39, 12341, Version of Record online: 12 SEP 2014

    2. N-Heterocyclic Carbenes

      A 4,5-Diphosphino-Substituted Imidazolium Salt: A Building Block for the Modular Synthesis of Mixed Diphosphine–NHC Heterometallic Complexes (pages 4485–4488)

      Prof. Javier Ruiz and Alejandro F. Mesa

      Version of Record online: 7 MAR 2012 | DOI: 10.1002/chem.201200031

      Thumbnail image of graphical abstract

      Fused in the same molecule! An N-heterocyclic carbene and a diphosphine are generated and used in the modular synthesis of a variety of target heterometallic complexes. The experimental approach involves formation of a unique 4,5-bis(diphenylphosphino)-1,3-dimethyl-imidazolium salt, simply by starting from 1-methylimidazole (see scheme; M1=Cr, Mn; M2=Au, Rh, Pd; LiHMDS=LiN(SiMe3)2).

    3. Battery Technology

      Improved Lithium Cyclability and Storage in Mesoporous SnO2 Electronically Wired with Very Low Concentrations (≤1 %) of Reduced Graphene Oxide (pages 4489–4494)

      Konda Shiva, H. B. Rajendra, K. S. Subrahmanyam, Dr. Aninda J. Bhattacharyya and Prof. C. N. R. Rao

      Version of Record online: 13 MAR 2012 | DOI: 10.1002/chem.201200352

      Thumbnail image of graphical abstract

      On the wire: Mesoporous tin dioxide (SnO2) wired with very low amounts (≤1 %) of reduced graphene oxide (rGO) exhibits a remarkable improvement in lithium-ion battery performance over bare mesoporous or solid nanoparticles of SnO2 (see figure). Reversible lithium intercalation into SnO2/SnO over several cycles was demonstrated in addition to conventional reversible lithium storage by an alloying reaction.

    4. Platinum Catalysis

      Factors Controlling the Equilibrium of Pt-Catalyzed [1,2]- versus [1,3]-Acyloxy Migration (pages 4495–4498)

      Prof. Dr. Eun Jin Cho

      Version of Record online: 12 MAR 2012 | DOI: 10.1002/chem.201103799

      Thumbnail image of graphical abstract

      Pick a pathway: Upon activation with an electrophilic transition-metal catalyst, a propargylic acetate undergoes competing [1,2]- and [1,3]-acyloxy migration depending on the reaction temperature as well as the substituent pattern around the alkyne. The nature of the catalyst also affects the reaction course. The reactions provided clear evidence for the interconversion between carbenoid and allene intermediates (see scheme).

    5. Platinum-Catalysed Bisindolylation of Allenes: A Complementary Alternative to Gold Catalysis (pages 4499–4504)

      Dr. María Paz Muñoz, Dr. María C. de la Torre and Prof. Miguel Angel Sierra

      Version of Record online: 13 MAR 2012 | DOI: 10.1002/chem.201103337

      Thumbnail image of graphical abstract

      Pt versus Au: Platinum-catalysed addition of nucleophiles to allenes follows a distinctly different pathway to the process catalysed by gold(I) complexes; the platinum catalyst leads to different products with indoles involving a bisindolylation reaction, whereas gold(I) gives allyl indoles from a single addition (see scheme).

    6. Polymer Networks

      Guest-Responsive Reversible Swelling and Enhanced Fluorescence in a Super-Absorbent, Dynamic Microporous Polymer (pages 4505–4509)

      K. Venkata Rao, Sudip Mohapatra, Dr. Tapas Kumar Maji and Dr. Subi J. George

      Version of Record online: 7 MAR 2012 | DOI: 10.1002/chem.201103750

      Thumbnail image of graphical abstract

      A swell idea! The guest-responsive reversible swelling and fluorescence enhancement of a dynamic, microporous polymer network is presented. Guest-induced breathing of hydrophobic pores imparts multi-functional properties, such as super-absorbency, phase-selective swelling of oil from water and encapsulation of C60 (see figure), to this soft micro-porous organic polymer.

    7. Boron Clusters

      Disk Aromaticity of the Planar and Fluxional Anionic Boron Clusters B20−/2− (pages 4510–4512)

      Truong Ba Tai, Prof. Dr. Arnout Ceulemans and Prof. Dr. Minh Tho Nguyen

      Version of Record online: 12 MAR 2012 | DOI: 10.1002/chem.201104064

      Thumbnail image of graphical abstract

      The presence of excess electrons modifies the structural landscape and tends to extend the planarity of boron clusters. While the neutral B20 is tubular, both the anion and dianion B20−/2− become planar. Geometrical features of the stable anions suggest the existence of a new type of cluster that is planar and doubly cyclic with one atom located at the center (see figure), as well as being fluxional.

    8. Sensors

      A Boradiazaindacene-Based Turn-On Fluorescent Probe for Cyanide Detection in Aqueous Media (pages 4513–4516)

      Chi-Hwa Lee, Hee-Jae Yoon, Jeong-Soo Shim and Prof. Woo-Dong Jang

      Version of Record online: 13 MAR 2012 | DOI: 10.1002/chem.201200008

      Thumbnail image of graphical abstract

      Turn on events: A molecular probe consisting of a boradiazaindacene unit conjugated with a dicyano-vinyl group has been designed for the selective and sensitive detection of cyanide by strong fluorescence enhancement in aqueous media (see scheme).

    9. Cross-Coupling

      [Pd(IPr*)(cinnamyl)Cl]: An Efficient Pre-catalyst for the Preparation of Tetra-ortho-substituted Biaryls by Suzuki–Miyaura Cross-Coupling (pages 4517–4521)

      Dr. Anthony Chartoire, Mathieu Lesieur, Laura Falivene, Prof. Dr. Alexandra M. Z. Slawin, Prof. Dr. Luigi Cavallo, Dr. Catherine S. J. Cazin and Prof. Dr. Steven P. Nolan

      Version of Record online: 13 MAR 2012 | DOI: 10.1002/chem.201104009

      Thumbnail image of graphical abstract

      The bigger the better: The new well-defined [Pd(IPr*)(cin)Cl] pre-catalyst is described (see scheme). This complex proves to be highly active in the Suzuki–Miyaura cross-coupling for the synthesis of tetra-ortho-substituted biaryls under mild conditions. IPr* is reported as the largest N-heterocyclic carbene (NHC) to date for [Pd(NHC)(cin)Cl] complexes, explaining the high reactivity observed for this complex in this challenging transformation.

  8. Full Papers

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. Fluorescent Compounds

      You have full text access to this OnlineOpen article
      Design and Synthesis of Fluorescent Pilicides and Curlicides: Bioactive Tools to Study Bacterial Virulence Mechanisms (pages 4522–4532)

      Dr. Erik Chorell–, Jerome S. Pinkner, Christoffer Bengtsson, Sofie Edvinsson, Dr. Corinne K. Cusumano, Dr. Erik Rosenbaum, Prof. Dr. Lennart B. Å. Johansson, Prof. Dr. Scott J. Hultgren and Prof. Dr. Fredrik Almqvist

      Version of Record online: 16 MAR 2012 | DOI: 10.1002/chem.201103936

      Thumbnail image of graphical abstract

      Lighting up bacterial virulence: Fluorescent pilicides and curlicides have been synthesized. This was achieved by using a strategy based on structure–activity knowledge in which key pilicide and curlicide substituents were replaced by fluorophores. Several of the resulting fluorescent compounds had improved activities as measured in pili- and curli-dependent biofilm assays and discriminate between different bacteria in a population (see figure).

    2. Bond Energy

      Bonding in a Borylene Complex Investigated by Photoionization and Dissociative Photoionization (pages 4533–4540)

      Dipl.-Chem. Kathrin H. Fischer, Dr. Michael Schneider, Prof. Dr. Ingo Fischer, Dipl.-Chem. Bernd Pfaffinger, Prof. Dr. Holger Braunschweig, Prof. Dr. Bálint Sztáray and Dr. Andras Bodi

      Version of Record online: 15 MAR 2012 | DOI: 10.1002/chem.201103993

      Thumbnail image of graphical abstract

      Breaking borylene: The photoionization of the borylene complex [(OC)5Cr[DOUBLE BOND]B[DOUBLE BOND]N(SiMe3)2] (see figure) has been studied by using synchrotron radiation. A sequential loss of CO groups is observed and ionic bond dissociation energies have been derived from a fit based on statistical theories. The results show that boron compounds with a low vapor pressure are amenable to thermochemical studies based on photoionization.

    3. Graphene

      On Oxygen-Containing Groups in Chemically Modified Graphenes (pages 4541–4548)

      Dr. Alessandra Bonanni, Dr. Adriano Ambrosi and Prof. Martin Pumera

      Version of Record online: 13 MAR 2012 | DOI: 10.1002/chem.201104003

      Thumbnail image of graphical abstract

      On the GO: The oxygen-containing groups on various chemically modified graphenes are comprehensively characterized by a wide variety of methods, such as high-resolution X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, UV/Vis spectroscopy, TEM, and voltammetry. Their positions on the sheet are identified by gold nanoparticle labels.

    4. Molecular Diagnostics

      A Way to Stable, Highly Emissive Fluorubine Dyes: Tuning the Electronic Properties of Azaderivatives of Pentacene by Introducing Substituted Pyrazines (pages 4549–4557)

      Dr. Jan Fleischhauer, Dr. Stefan Zahn, Prof. Dr. Rainer Beckert, Prof. Dr. Ulrich-Walter Grummt, Dr. Eckhard Birckner and Dr. Helmar Görls

      Version of Record online: 5 MAR 2012 | DOI: 10.1002/chem.201103350

      Thumbnail image of graphical abstract

      Tune your pentacene: Novel quinoidal and mesoionic dihydro-hexaazapentacenes have been synthesised, characterised and their photophysical properties were investigated (see figure; red: CH2Cl2; black: AcOH, Ac=acyl; blue: HCl (36 %)). Exceptional optical and electronical properties in conjunction with high fluorescence quantum yields and marked solid state properties make them promising candidates for molecular diagnostics or n-type devices.

    5. Donor–Acceptor Systems

      Design and Synthesis of Piezochromic Materials Based on Push–Pull Chromophores: A Mechanistic Perspective (pages 4558–4567)

      Fengkun Chen, Dr. Jie Zhang and Prof. Xinhua Wan

      Version of Record online: 5 MAR 2012 | DOI: 10.1002/chem.201102929

      Thumbnail image of graphical abstract

      Like a chameleon: Based on molecular modeling results, a series of anthraquinone imide derivatives with different electron-donating/-withdrawing substituents were designed and prepared to verify the hypothesis that piezochromism observed in this series of compounds resulted from enhanced intramolecular charge transfer (see picture).

    6. Chemo-Mechanical Tweezers

      A Chemo-Mechanical Tweezer for Single-Molecular Characterization of Soft Materials (pages 4568–4574)

      Dr. Jun Guo, Dr. Guojun Chen, Dr. Xinghai Ning, Dr. Xiuru Li, Dr. Jianfeng Zhou, Dr. Anna Jagielska, Prof. Bingqian Xu and Prof. Geert-Jan Boons

      Version of Record online: 28 FEB 2012 | DOI: 10.1002/chem.201102947

      Thumbnail image of graphical abstract

      Azide imaging: An atomic force microscopy (AFM)-based chemo-mechanical tweezer has been developed that can measure mechanical properties of individual macromolecules in a supramolecular assembly, revealing positions of azide-containing polymers and providing topographical images with a high-resolution surface. A key feature of the new technology is the use of an AFM tip densely modified with 4-dibenzocyclooctynols (see figure).

    7. Nanoparticles

      A One-Step Process for the Antimicrobial Finishing of Textiles with Crystalline TiO2 Nanoparticles (pages 4575–4582)

      Dr. Ilana Perelshtein, M.Sc. Guy Applerot, Dr. Nina Perkas, Judith Grinblat and Prof. Aharon Gedanken

      Version of Record online: 8 MAR 2012 | DOI: 10.1002/chem.201101683

      Thumbnail image of graphical abstract

      A big finish: Titanium oxide (TiO2) nanoparticles (NPs) in their two forms, anatase and rutile, were synthesized and deposited onto the surface of cotton fabrics by using ultrasonic irradiation. The antimicrobial activities of the TiO2–cotton composites were tested against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) strains, as well as against Candida albicans.

    8. Structure Elucidation

      Structure of Sodiated Polyglycines (pages 4583–4592)

      Dr. O. Petru Balaj, Dr. David Semrouni, Vincent Steinmetz, Edith Nicol, Dr. Carine Clavaguéra and Dr. Gilles Ohanessian

      Version of Record online: 2 MAR 2012 | DOI: 10.1002/chem.201102812

      Thumbnail image of graphical abstract

      Wrapped! Polyglycine peptides (Gn) wrapped around a sodium ion were investigated in detail by using IRMPD spectroscopy (see figure) and molecular modeling. Smaller values of n favor exclusive metal–peptide interactions at all amide oxygen atoms, whereas for n>6 a delicate balance is established with the internal peptide hydrogen-bond network.

    9. Platinum Chemistry

      Synthesis, Structural Characterization, Photophysics, and Broadband Nonlinear Absorption of a Platinum(II) Complex with the 6-(7-Benzothiazol-2′-yl-9,9-diethyl-9 H-fluoren-2-yl)-2,2′-bipyridinyl Ligand (pages 4593–4606)

      Dr. Bingguang Zhang, Dr. Yunjing Li, Dr. Rui Liu, Dr. Timothy M. Pritchett, Dr. Alexander Azenkeng, Dr. Angel Ugrinov, Dr. Joy E. Haley, Zhongjing Li, Dr. Mark R. Hoffmann and Dr. Wenfang Sun

      Version of Record online: 8 MAR 2012 | DOI: 10.1002/chem.201103095

      Thumbnail image of graphical abstract

      Structure–absorption relationships: The platinum(II) complex with the 6-(7-benzothiazol-2′-yl-9,9-diethyl-9H-fluoren-2-yl)- 2,2′-bipyridinyl ligand possesses large ratios of excited-state absorption cross sections relative to that of the ground state in the visible spectral region and is among the strongest two-photon-absorbing platinum complexes in the near-IR region (see figure).

    10. Polymerization

      Copper-Mediated Controlled/“Living” Radical Polymerization in Polar Solvents: Insights into Some Relevant Mechanistic Aspects (pages 4607–4612)

      Dr. Tamaz Guliashvili, Patrícia V. Mendonça, Dr. Arménio C. Serra, Dr. Anatoliy V. Popov and Dr. Jorge F. J. Coelho

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201102183

      Thumbnail image of graphical abstract

      Copper(I) is the activator! The CuIBr/Me6TREN ratio (Me6TREN=tris[2-(dimethylamino)ethyl]amine) and the extent of CuIBr/Me6TREN disproportionation were determined, for the first time, under real polymerization conditions. The results (see figure) clearly revealed that [CuIBr/Me6TREN] species are the most probable activators of single-electron transfer living radical polymerization (SET-LRP), whereas Cu0 acts as a supplemental activator and reducing agent of CuIIBr2/Me6TREN.

    11. Mass Spectrometry

      You have full text access to this OnlineOpen article
      Formation and Decay of the Dehydrogenated Parent Anion upon Electron Attachment to Dialanine (pages 4613–4619)

      David Gschliesser, Dr. Violaine Vizcaino, Prof. Michael Probst, Prof. Paul Scheier and Prof. Stephan Denifl

      Version of Record online: 28 FEB 2012 | DOI: 10.1002/chem.201102433

      Thumbnail image of graphical abstract

      Which site is it? The severe dissociation of biomolecules after free-electron capture may proceed, after initial hydrogen loss, in the formation of a negative ion. In this study, the possible sites of this hydrogen loss are investigated for the dipeptide dialanine by utilizing a high-resolution electron beam (see figure). The subsequent dissociation pathways of the dissociation intermediates are also determined.

    12. Photocatalysts

      Polyhedral AgBr Microcrystals with an Increased Percentage of Exposed {111} Facets as a Highly Efficient Visible-Light Photocatalyst (pages 4620–4626)

      Dr. Hua Wang, Xiufeng Lang, Jian Gao, Wei Liu, Di Wu, Dr. Yongmin Wu, Prof. Lin Guo and Prof. Jinghong Li

      Version of Record online: 5 MAR 2012 | DOI: 10.1002/chem.201102694

      Thumbnail image of graphical abstract

      Making light work: Polyhedral AgBr microcrystals are prepared by a modified ion-exchange method, and their performance as an AgBr/Ag plasmonic photocatalyst is investigated. The as-prepared sample has high photocatalytic activity, which can be attributed to the relatively high surface reactivities of AgBr {111} facets (see figure).

    13. Heterocycles

      Synthesis and Optical Properties of Diaza- and Tetraazatetracenes (pages 4627–4633)

      Dipl. Chem. Benjamin D. Lindner, Dipl. Chem. Jens U. Engelhart, Michaela Märken, Olena Tverskoy, Dr. Anthony L. Appleton, Dr. Frank Rominger, Dr. Kenneth I. Hardcastle, Prof. Markus Enders and Prof. Uwe H. F. Bunz

      Version of Record online: 16 FEB 2012 | DOI: 10.1002/chem.201103227

      Thumbnail image of graphical abstract

      A colorful bunch of heteroacenes were prepared by direct condensation of diamines with ortho-quinones or by Pd-catalyzed coupling of diamines to dichloroquinoxalines. The oligoazatetracenes displayed different colors depending upon their substitution patterns.

    14. Solid-State Fluorescence

      Regulation of π-Stacked Anthracene Arrangement for Fluorescence Modulation of Organic Solid from Monomer to Excited Oligomer Emission (pages 4634–4643)

      Tomoaki Hinoue, Yuta Shigenoi, Misa Sugino, Dr. Yuji Mizobe, Dr. Ichiro Hisaki, Prof. Dr. Mikiji Miyata and Dr. Norimitsu Tohnai

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201103518

      Thumbnail image of graphical abstract

      Crystal engineering: π-Stacked anthracene arrangements are regulated for fluorescence modulation in the crystalline state. Organic salts comprising anthracene-1,5-disulfonic acid and various aliphatic amines allow ready regulation of the arrangements adopted. It is demonstrated that the π-stacked arrangements of aromatic fluorophores (see figure) significantly affect the luminescence process (from monomer to excited oligomer emission) and corresponding photophysical properties of organic solids.

    15. C[BOND]H Activation

      Tautomerisation of 2-Substituted Pyridines to N-Heterocyclic Carbene Ligands Induced by the 16 e Unsaturated [TpMe2IrIII(C6H5)2] Moiety (pages 4644–4664)

      Dr. Salvador Conejero, Dr. Joaquín López-Serrano, Prof. Dr. Margarita Paneque, Dr. Ana Petronilho, Prof. Dr. Manuel L. Poveda, Florencia Vattier, Dr. Eleuterio Álvarez and Prof. Dr. Ernesto Carmona

      Version of Record online: 5 MAR 2012 | DOI: 10.1002/chem.201103507

      Thumbnail image of graphical abstract

      Shuttling a hydrogen atom: The complex [TpMe2Ir(C6H5)2(N2)] reacts with several 2-substituted pyridines to generate N-heterocyclic carbenes resulting from a formal 1,2-hydrogen shift from C6 to N (see scheme).

    16. Amine-Borane Dehydrogenation

      “Spontaneous” Ambient Temperature Dehydrocoupling of Aromatic Amine–Boranes (pages 4665–4680)

      Dr. Holger Helten, Alasdair P. M. Robertson, Prof. Dr. Anne Staubitz, James R. Vance, Dr. Mairi F. Haddow and Prof. Dr. Ian Manners

      Version of Record online: 5 MAR 2012 | DOI: 10.1002/chem.201103241

      Thumbnail image of graphical abstract

      Spontaneous hydrogen evolution: The structural chemistry and dehydrocoupling behavior of aniline–borane and related primary arylamine–borane adducts has been explored in detail for the first time. These labile donor–acceptor species have been found to undergo “spontaneous” loss of hydrogen without the need for an externally added catalyst. The reaction proceeds via a series of intermediates to yield cyclotriborazanes, borazines, and unexpected oligomeric products via mechanistic pathways of surprising complexity (see scheme).

    17. Hydrothermal Synthesis

      One-Pot Hydrothermal Synthesis of Heterostructured ZnO/ZnS Nanorod Arrays with High Ethanol-Sensing Properties (pages 4681–4686)

      Prof. Peng Gao, Longqiang Wang, Ying Wang, Prof. Yujin Chen, Xiaona Wang and Guoli Zhang

      Version of Record online: 8 MAR 2012 | DOI: 10.1002/chem.201102927

      Thumbnail image of graphical abstract

      Throwing the kitchen zinc: heterostructured ZnO/ZnS nanorod arrays with uniform diameter and length were synthesized from zinc substrates in a one-pot procedure by using a simple hydrothermal method. Structural characterization by HRTEM indicated that the nanorods were composed of parallel segment of wurtzite-type ZnO and zinc-blende ZnS, with a distinct interface along the axial direction.

    18. Alcohol Deoxygenation

      Highly Chemoselective Calcium-Catalyzed Propargylic Deoxygenation (pages 4687–4691)

      Vera J. Meyer and Prof. Dr. Meike Niggemann

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201103691

      Thumbnail image of graphical abstract

      Choose calcium for chemoselectivity: A calcium-catalyzed direct reduction of propargylic alcohols and ethers has been accomplished by using triethylsilane as a nucleophilic hydride source (see scheme). A variety of secondary propargylic alcohols were deoxygenated to the corresponding hydrocarbons at room temperature in excellent yields and high chemoselectivity. For the first time, the catalytic deoxygenation of tertiary propargylic alcohols was generally applicable.

    19. Sensors

      Molecularly Imprinted Shells from Polymer and Xerogel Matrices on Polystyrene Colloidal Spheres (pages 4692–4698)

      Dr. Guijian Guan, Renyong Liu, Qingsong Mei and Prof. Dr. Zhongping Zhang

      Version of Record online: 5 MAR 2012 | DOI: 10.1002/chem.201102576

      Thumbnail image of graphical abstract

      Capturing TNT: A versatile protocol for the synthesis of molecularly imprinted silica (MIS) and polymer (MIP) shells at the surface of polystyrene (PS) spheres was designed (see figure). The resultant microspheres exhibited high rebinding capacity and selectivity, as well as fast binding kinetics towards target species.

    20. Radicals

      On the Lifetime of the Transients (NP)[BOND](CH3)n (NP=Ag0, Au0, TiO2 Nanoparticles) Formed in the Reactions Between Methyl Radicals and Nanoparticles Suspended in Aqueous Solutions (pages 4699–4705)

      Ronen Bar-Ziv, Dr. Israel Zilbermann, Dr. Olga Oster-Golberg, Dr. Tomer Zidki, Guy Yardeni, Prof. Haim Cohen and Prof. Dan Meyerstein

      Version of Record online: 1 MAR 2012 | DOI: 10.1002/chem.201102671

      Thumbnail image of graphical abstract

      Long live the intermediate! Methyl radicals react in fast reactions with Au0, Ag0, and TiO2 nanoparticles (NPs) dispersed in aqueous solutions to form intermediates (NP)[BOND](CH3)n. The minimal lifetime (τ) of these intermediates is surprisingly long, for example, ≥8 and ≥188 seconds for silver and gold, respectively (see figure).

    21. Polymers

      Characterisation of Solute Mobility in Hypercross-Linked Resins in Solvents of Different Polarity: Two Promising Supports for Catalysis (pages 4706–4713)

      Dr. Marco Bortolus, Dr. Paolo Centomo, Prof. Marco Zecca, Dr. Alessandro Sassi, Dr. Karel Jeřábek, Prof. Anna Lisa Maniero and Prof. Benedetto Corain

      Version of Record online: 13 MAR 2012 | DOI: 10.1002/chem.201103994

      Thumbnail image of graphical abstract

      Modulating solute mobility: Two hypercross-linked polymers, synthesised from a gel-type precursor, are examined with specific absorbed solvent volume (SAV), EPR and time-domain (TD)-NMR techniques in solvents of different polarity to evaluate the solute mobility inside the polymer network (see figure). The mobility is found to depend markedly on the choice of the solvent, with THF allowing fast diffusion.

    22. Difunctionalisation

      You have full text access to this OnlineOpen article
      Transmetallation Versus β-Hydride Elimination: The Role of 1,4-Benzoquinone in Chelation-Controlled Arylation Reactions with Arylboronic Acids (pages 4714–4722)

      Dr. Christian Sköld, Jonatan Kleimark, Alejandro Trejos, Dr. Luke R. Odell, Dr. Sten O. Nilsson Lill, Prof. Per-Ola Norrby and Prof. Mats Larhed

      Version of Record online: 28 FEB 2012 | DOI: 10.1002/chem.201102678

      Thumbnail image of graphical abstract

      Electron greed! The back donation of electrons from PdII to 1,4-benzoquinone in a σ-alkyl complex is reported to have a decisive impact on the reaction pathway in an oxidative Heck reaction (see scheme). Energy calculations show that not only reductive elimination is promoted, but also transmetallation, which leads to the difunctionalised product by an oxidative Heck/Suzuki–Miyaura tandem reaction.

    23. Bridging Ligands

      Facile Carbon–Fluorine Bond Activation and Subsequent Functionalisation of 1,1-Difluoroethylene and Tetrafluoroethylene Promoted by Adjacent Metal Centres (pages 4723–4737)

      Michael E. Slaney, D. Jason Anderson, Dusan Ristic-Petrovic, Dr. Robert McDonald and Prof. Dr. Martin Cowie

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201101835

      Thumbnail image of graphical abstract

      Two metals are better than one: Facile C[BOND]F bond activation of tetrafluoroethylene- and 1,1-difluoroethylene-bridged complexes is observed. The 1,1-difluoroethylene-bridged complex can undergo C[BOND]F activation by reaction with trimethylsilyl triflate, carbon monoxide or water, giving a fluorovinyl-bridged product, a propynyl-bridged product and 2-fluoropropene, respectively (see scheme). The conversion of tetrafluoroethylene into trifluoroethylene is also observed.

    24. Mesoporous Materials

      Intrinsic Catalytic Role of Mesoporous Silica in Preferential Oxidation of Carbon Monoxide in Excess Hydrogen (pages 4738–4747)

      Dr. Shengjun Huang, Dr. Kenji Hara and Prof. Dr. Atsushi Fukuoka

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201102256

      Thumbnail image of graphical abstract

      Environmental factors: The catalytic role of MCM-41 mesoporous silica in the preferential oxidation of carbon monoxide in excess hydrogen closely relates to the microreactive environment at the interface between Pt and MCM-41. It is shown that interfacial silanols on Pt/MCM-41 initiate CO oxidation and sustain the dissociation of O2 on the CO-free Pt sites created by the interface reactions (see figure).

    25. Gold Catalysis

      Gold- and Silver-Catalyzed Reactions of Propargylic Alcohols in the Presence of Protic Additives (pages 4748–4758)

      Matthew N. Pennell, Dr. Peter G. Turner and Dr. Tom D. Sheppard

      Version of Record online: 28 FEB 2012 | DOI: 10.1002/chem.201102830

      Thumbnail image of graphical abstract

      Enones made easy: Primary, secondary and tertiary propargylic alcohols undergo an efficient Au-catalyzed Meyer–Schuster rearrangement, in the presence of protic additives. The rearrangement of primary alcohols can be combined with the addition of nucleophiles to the resulting enone to give β-substituted ketones in a one-pot procedure. Electron-rich propargylic alcohols undergo Ag-catalyzed substitution with a variety of oxygen, carbon and nitrogen nucleophiles (see scheme).

    26. Titanium

      Size-Dependent Surface Activity of Rutile and Anatase TiO2 Nanocrystals: Facile Surface Modification and Enhanced Photocatalytic Performance (pages 4759–4765)

      Dr. Guolei Xiang, Dr. Yang-Gang Wang, Di Wu, Dr. Tianyang Li, Dr. Jie He, Prof. Jun Li and Prof. Xun Wang

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201102593

      Thumbnail image of graphical abstract

      Good things come in small packages: The size dependence of the surface activity of titania was investigated through the formation of ultrafine nanocrystals, the surfaces of which were modified by organic molecules in a facile manner, and which exhibited enhanced dispersity in various solvents, strong visible-light absorption through coordination with peroxide, and enhanced photocatalytic performance (see figure).

    27. Natural Products

      Photooxygenation of a Microbial Arene Oxidation Product and Regioselective Kornblum–DeLaMare Rearrangement: Total Synthesis of Zeylenols and Zeylenones (pages 4766–4774)

      Dr. Matthew J. Palframan, Dr. Gabriele Kociok-Köhn and Dr. Simon E. Lewis

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201104035

      Thumbnail image of graphical abstract

      New light on a Korny rearrangement: Biooxidation of benzoic acid with R. eutrophus B9 gives a dearomatised diene diol acid that allows concise access to the zeylenol and zeylenone family of polyoxygenated cyclohexene natural products. The synthesis employs diene photooxygenation and a new regioselective variant of the Kornblum–DeLaMare endoperoxide fragmentation has been developed (see scheme).

    28. Desulfurization

      Highly Efficient Extraction and Oxidative Desulfurization System Using Na7H2LaW10O36⋅32 H2O in [bmim]BF4 at Room Temperature (pages 4775–4781)

      Junhua Xu, Shen Zhao, Wei Chen, Miao Wang and Prof. Yu-Fei Song

      Version of Record online: 28 FEB 2012 | DOI: 10.1002/chem.201102754

      Thumbnail image of graphical abstract

      Deep desulfurization of model oil containing dibenzothiophene, benzothiophene, or 4,6-dimethyldibenzothiophene has been achieved under mild conditions by utilizing polyoxometalate Na7H2LaW10O3632 H2O (LaW10) as catalyst, [bmim]BF4 as extractant, and H2O2 as oxidant (see figure). The LaW10/[bmim]BF4 system shows superior desulfurization efficiency compared with other systems in ionic liquids (bmim=1-butyl-3-methylimidazolium).

    29. Anion Binding

      Amidetriazole: A Versatile Building Block for Construction of Oxyanion Anion Receptors (pages 4782–4790)

      Dr. Yong-Jun Li, Liang Xu , Wen-Long Yang , Dr. Hui-Biao Liu, Siu-Wai Lai, Prof. Chi-Ming Che and Prof. Yu-Liang Li

      Version of Record online: 29 FEB 2012 | DOI: 10.1002/chem.201102760

      Thumbnail image of graphical abstract

      Simple, but efficient! Amidetriazole, a versatile building block that combines the characteristics of urea and 1,2,3-triazole, shows great potential for the construction of tetrahedral oxyanion receptors (see figure).

  9. Preview

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Concept
    7. Essay
    8. Communications
    9. Full Papers
    10. Preview
    1. You have free access to this content
      Preview: Chem. Eur. J. 16/2012 (page 4795)

      Version of Record online: 30 MAR 2012 | DOI: 10.1002/chem.201290059

SEARCH

SEARCH BY CITATION