Angewandte Chemie International Edition

Cover image for Vol. 49 Issue 29

July 5, 2010

Volume 49, Issue 29

Pages 4839–5011

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
    9. Review
    10. Communications
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    1. Cover Picture: Sensitive and Selective Chromogenic Sensing of Carbon Monoxide by Using Binuclear Rhodium Complexes (Angew. Chem. Int. Ed. 29/2010) (page 4839)

      Julio Esteban, José Vicente Ros-Lis, Ramón Martínez-Máñez, M. Dolores Marcos, María Moragues, Juan Soto and Félix Sancenón

      Version of Record online: 8 JUN 2010 | DOI: 10.1002/anie.201002976

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      Like in a collage by Max Ernst, a combination of a known molecular entity (a binuclear rhodium complex) and suitable bridging ligands can take on a new role as a chromogenic chemosensor. R. Martínez-Máñez and co-workers describe in their Communication on page 4934 ff. how the color change these complexes undergo allows them to act as a carbon monoxide sensor.

  2. Inside Cover

    1. Top of page
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    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
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    10. Communications
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    1. Inside Cover: Monodisperse Yolk–Shell Nanoparticles with a Hierarchical Porous Structure for Delivery Vehicles and Nanoreactors (Angew. Chem. Int. Ed. 29/2010) (page 4840)

      Jian Liu, Shi Zhang Qiao, Sandy Budi Hartono and Gao Qing (Max) Lu

      Version of Record online: 11 JUN 2010 | DOI: 10.1002/anie.201002660

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      A yolk–shell structure with a distinctive core@void@shell configuration is synthesized using a facile vesicle template strategy. S. Z. Qiao, G. Q. Lu, and co-workers describe in their Communication on page 4981 ff. how the size of both core and shell are tunable. In addition, loading these mesoporous materials with gold nanocatalysts and their drug-release capability were investigated.

  3. Graphical Abstract

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
    9. Review
    10. Communications
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  4. News

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
    9. Review
    10. Communications
    11. Preview
  5. Book Reviews

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
    9. Review
    10. Communications
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    1. Two-Dimensional X-Ray Diffraction . By Bob B. He. (pages 4858–4859)

      Christian W. Lehmann

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.200906208

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      John Wiley & Sons, Hoboken 2009. 426 pp., hardcover € 97.90.—ISBN 978-0470227220

    2. Giant Molecules. From Nylon to Nanotubes. By Walter Gratzer. (page 4859)

      Fredric M. Menger

      Version of Record online: 11 JUN 2010 | DOI: 10.1002/anie.201003186

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      Oxford University Press, Oxford 2009. 254 pp., hardcover € 14.99.—ISBN 978-0199550029

  6. Highlight

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
    9. Review
    10. Communications
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    1. Silicon Chemistry

      News from Silicon: An Isomer of Hexasilabenzene and A Metal–Silicon Triple Bond (pages 4860–4862)

      Claudia Gerdes and Thomas Müller

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.201001558

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      Elegant synthesis! Recent progress in synthetic methods has allowed the preparation and isolation of novel silicon compounds with multiple bonds. A cyclic conjugated isomer 1 of the elusive hexasilabenzene and a silylidyne complex 2 with a genuine molybdenum–silicon triple bond have been synthesized.

  7. Essay

    1. Top of page
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    4. Graphical Abstract
    5. News
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    8. Essay
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    10. Communications
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    1. History of Chemistry

      From Discovery to Application: 50 Years of the Vinylcyclopropane–Cyclopentene Rearrangement and Its Impact on the Synthesis of Natural Products (pages 4864–4876)

      Tomas Hudlicky and Josephine W. Reed

      Version of Record online: 16 JUN 2010 | DOI: 10.1002/anie.200906001

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      A classic that hasn't lost its charm: The historical origins and current status of the vinylcyclopropane–cyclopentene rearrangement and the corresponding transformations of heteroatom-containing analogues (see scheme) are described in the context of methodology development and natural products synthesis. Several important events that greatly influenced the author's own research program some 30 to 40 years ago are recounted as personal recollections.

  8. Review

    1. Top of page
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    8. Essay
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    10. Communications
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    1. Multicomponent Nanoparticles

      Colloidal Hybrid Nanostructures: A New Type of Functional Materials (pages 4878–4897)

      Ronny Costi, Aaron E. Saunders and Uri Banin

      Version of Record online: 11 JUN 2010 | DOI: 10.1002/anie.200906010

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      One goal of nanocrystal research is the development of methods to control composition and shape. The ability to selectively arrange nanosized domains of metallic, semiconducting, and magnetic materials into a hybrid nanoparticle offers a route to nanomaterials with multiple functionalities or the enhanced properties of one domain. This Review focuses on recent synthetic strategies, properties, and applications of semiconductor–metal hybrid nanoparticles.

  9. Communications

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
    9. Review
    10. Communications
    11. Preview
    1. Keto–Enol Tautomerization

      Catalytic Action of a Single Water Molecule in a Proton-Migration Reaction (pages 4898–4901)

      Yoshiyuki Matsuda, Ayako Yamada, Ken-ichi Hanaue, Naohiko Mikami and Asuka Fujii

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.201001364

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      Baby steps: The mechanism of proton migration in an ionized acetone–water cluster was studied by IR spectroscopy. After the ionization, water abstracts a proton from the methyl group of the acetone moiety and transfers it to the carbonyl group (see picture).

    2. Nanocomposite Fluid

      Synthesis of Transparent and Field-Responsive BaTiO3 Particle/Organosiloxane Hybrid Fluid (pages 4902–4906)

      Ken-ichi Mimura, Yuki Nishimoto, Hiroshi Orihara, Makoto Moriya, Wataru Sakamoto and Toshinobu Yogo

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201001398

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      A smart fluid containing BaTiO3 nanoparticles was synthesized by a chemical solution process. The transparent and homogeneous fluid (see picture) changes its rheological properties in response to an electric field. Formation of aligned structures from nanoparticles under shear stress (arrow) was confirmed by 3D confocal fluorescence microscopy (white dots: fluorescein-modified nanoparticles).

    3. Oxygen Detection

      Photographing Oxygen Distribution (pages 4907–4909)

      Xu-dong Wang, Robert J. Meier, Martin Link and Otto S. Wolfbeis

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201001305

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      O2, where are you? The spatial distribution of oxygen can be imaged with a conventional digital camera by making use of a specially designed fluorescent sensor film containing a quenchable red-emitting probe for oxygen along with a green-emitting reference fluorophore. The technique exploits the RGB channels involved in digital photography (see picture) to deliver a simple method for quantitative sensing and imaging of this important species.

      Corrected by:

      Corrigendum: Corrigendum: Photographing Oxygen Distribution

      Vol. 49, Issue 37, 6475, Version of Record online: 1 SEP 2010

    4. Supramolecular Chirality

      Orthogonal Action of Noncovalent Interactions for Photoresponsive Chiral Columnar Assemblies (pages 4910–4914)

      Francisco Vera, Joaquín Barberá, Pilar Romero, José Luis Serrano, M. Blanca Ros and Teresa Sierra

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201000580

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      Making a stack: Helical columnar architectures are prepared by a hierarchical self-assembly process involving H-bonding, π–π, and ion–dipole interactions (see picture). The strategic combination of these supramolecular interactions within mesomorphic systems yields materials in which photoinduced chirality and the incorporation of ions can be used to design multifunctional liquid crystals.

    5. Sensors

      A Rapid Aqueous Fluoride Ion Sensor with Dual Output Modes (pages 4915–4918)

      Rui Hu, Jiao Feng, Dehui Hu, Shuangqing Wang, Shayu Li, Yi Li and Guoqiang Yang

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201000790

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      The color purple: A siloxy-functionalized benzamide (see picture) is a highly efficient fluoride ion sensor in water. The sensor, which is activated when the O[BOND]Si bond is cleaved by fluoride ions, provides two independent modes for signal recognition. In colorimetric mode, the fluoride ion concentration is transformed into a fluorescence signal that can be observed directly with the naked eye.

    6. Kinase Assay

      Detection of Kinase Activity Using Versatile Fluorescence Quencher Probes (pages 4919–4923)

      Hyun-Woo Rhee, Seung Hwan Lee, Ik-Soo Shin, So Jung Choi, Hun Hee Park, Kyungja Han, Tai Hyun Park and Jong-In Hong

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201000879

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      Turn off the light! A kinase assay system employs fluorescent peptides and a phosphate-selective fluorescence quencher probe, and can be placed on a microfluidic chip (see picture). The system can be used for real-time kinase monitoring, kinase inhibitor screening, and cancer diagnosis based on abnormal kinase activity observed in patients' samples.

    7. Cluster Compounds

      {[Ag42(CO3)(C[TRIPLE BOND]CtBu)27(CH3CN)2][CoW12O40]2}[BF4]: An Intercluster Sandwich Compound (pages 4924–4926)

      Franziska Gruber and Martin Jansen

      Version of Record online: 8 JUN 2010 | DOI: 10.1002/anie.201001104

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      The Earl of Sandwich: The first intercluster sandwich compound was obtained from silver alkynyl clusters and [CoW12O40]6− in a one-pot reaction. The silver block has a toroidal shape with direct contacts to two polyoxometalate anions, which close its open ends.

    8. DNA Nanomaterials

      Antiferromagnetic Coupling of Stacked CuII–Salen Complexes in DNA (pages 4927–4929)

      Guido H. Clever, Stephan J. Reitmeier, Thomas Carell and Olav Schiemann

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.200906359

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      A pretty couple: Two copper–salen metal–base pairs were incorporated into a DNA double helix in neighboring positions (see picture). The two paramagnetic CuII ions are antiferromagnetically coupled, and the exchange coupling constant is −2J=22.4 cm−1. The dipolar coupling constant yielded a Cu⋅⋅⋅Cu distance of 3.7 Å, which is comparable to the base-pair distance in natural B-type DNA.

    9. Drug Delivery

      A Protease-Based Strategy for the Controlled Release of Therapeutic Peptides (pages 4930–4933)

      Hongjian Li, Yi Ma, Ying Chen, Yanxia Sang, Tianhong Zhou, Meilan Qiu, Xiumei Huang, Cindy Zhou and Zhengding Su

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201000287

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      A polypeptide containing an albumin-binding domain (ABD), an amino acid sequence linker, and glucagon-like peptide-1 (GLP-1), a potential antidiabetic agent, is designed to slowly release GLP-1 through sequential cleavage by native plasma proteases (see picture). The half-life of the polypeptide in the bloodstream is extended by its association with human serum albumin (HSA).

    10. Sensors

      Sensitive and Selective Chromogenic Sensing of Carbon Monoxide by Using Binuclear Rhodium Complexes (pages 4934–4937)

      Julio Esteban, José Vicente Ros-Lis, Ramón Martínez-Máñez, M. Dolores Marcos, María Moragues, Juan Soto and Félix Sancenón

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.201001344

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      CO-catcher: Carbon monoxide can be detected selectively and sensitively by the binuclear rhodium complex cis-[Rh2(C6H4PPh2)2(O2CCH3)2](HO2CCH3)2. This complex, which contains two cyclometalated phosphine ligands, coordinates CO axially and undergoes a color change from violet to orange-yellow (see picture).

    11. Molecular Switches

      A [2]Rotaxane Flip Switch Driven by Coordination Geometry (pages 4938–4942)

      Gregory J. E. Davidson, Sapna Sharma and Stephen J. Loeb

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201001486

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      The carrot is better than the stick! Changes in the metal coordination geometry of the capping group in a [2]rotaxane ligand results in molecular switching by reorienting a trapped macrocyclic component (see picture). Switching was successfully initiated when the metal coordination site was made more attractive (square planar), but not when the metal coordination site was made less attractive (octahedral).

    12. Metallacarboranes

      Room-Temperature C[BOND]C Bond Cleavage of an Arene by a Metallacarborane (pages 4943–4945)

      David Ellis, David McKay, Stuart A. Macgregor, Georgina M. Rosair and Alan J. Welch

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201001555

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      On the fly: Reduction of 1,1′-bis(o-carborane) and subsequent reaction with a source of {Ru(p-cymene)}2+ fragments yields a fly-over bridge species resulting from room-temperature C[BOND]C bond cleavage of a p-cymene ligand. DFT calculations suggest that the arene is sandwiched between two Ru atoms as part of a metallacarborane (see picture; C gray, B yellow, Ru red) and reduced by the second, pendant, carborane.

    13. Functional Protein Coatings

      Interfacial Engineering by Proteins: Exfoliation and Functionalization of Graphene by Hydrophobins (pages 4946–4949)

      Päivi Laaksonen, Markku Kainlauri, Timo Laaksonen, Andrey Shchepetov, Hua Jiang, Jouni Ahopelto and Markus B. Linder

      Version of Record online: 8 JUN 2010 | DOI: 10.1002/anie.201001806

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      Simply peel off the layers: Functionalities from nature may be used to meet the demands of contemporary materials science in terms of the efficient and safe production of high-quality, versatile materials. Thus, the spontaneous absorption on graphite of small amphiphilic proteins known as hydrophobins from an aqueous phase, followed by sonication, led to the exfoliation and stabilization of graphene sheets (see picture).

    14. Aromaticity

      Möbius Antiaromatic Bisphosphorus Complexes of [30]Hexaphyrins (pages 4950–4954)

      Tomohiro Higashino, Jong Min Lim, Takahiro Miura, Shohei Saito, Jae-Yoon Shin, Dongho Kim and Atsuhiro Osuka

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.201001765

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      Aromaticity with a twist: The reversal of Möbius aromaticity occurs by changing the number of π electrons between [4n+2] and [4n] in monophosphorus complexes of [28]hexaphyrins and bisphosphorus complexes of [30]hexaphyrins. The 30π Möbius antiaromatic bisphosporus[30]hexaphyrins (see picture) were determined to be the first structurally characterized Möbius antiaromatic systems, which are rigid, neutral, and stable.

    15. Asymmetric Synthesis

      Nickel-Catalyzed Regio- and Enantioselective Annulation Reactions of 1,2,3,4-Benzothiatriazine-1,1(2H)-dioxides with Allenes (pages 4955–4957)

      Tomoya Miura, Motoshi Yamauchi, Akira Kosaka and Masahiro Murakami

      Version of Record online: 8 JUN 2010 | DOI: 10.1002/anie.201001918

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      Extrusion of N2: 1,2,3,4-Benzothiatriazine-1,1(2H)-dioxides reacted with allenes in the presence of a nickel(0)/(R)-quinap complex to produce a variety of substituted 3,4-dihydro-1,2-benzothiazine-1,1(2H)-dioxides in a regio- and enantioselective fashion. An intermediate nickelacycle was generated through denitrogenative activation of the triazo moiety which allowed the intermolecular incorporation of an allene group. quinap=1-(2-diphenylphosphino-1-naphthyl)isoquinoline.

    16. Microporous Membranes

      Molecular-Sieve Membrane with Hydrogen Permselectivity: ZIF-22 in LTA Topology Prepared with 3-Aminopropyltriethoxysilane as Covalent Linker (pages 4958–4961)

      Aisheng Huang, Helge Bux, Frank Steinbach and Jürgen Caro

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201001919

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      High hydrogen selectivity and thermal stability are displayed by a membrane of zeolitic imidazolate ZIF-22 grown on porous ceramic supports by using 3-aminopropyltriethoxysilane (APTES) as covalent linker (see picture). At 323 K, H2/CO2 selectivity of 7.2 and H2 permeance of 1.6×10−7 mol m−2 s−1 Pa−1 were achieved.

    17. Nanoflowers

      A Universal Approach to the Synthesis of Noble Metal Nanodendrites and Their Catalytic Properties (pages 4962–4966)

      Ashok Mohanty, Niti Garg and Rongchao Jin

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.201000902

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      Flower power: A universal approach is presented for high-yield synthesis of Au, Pt, and Pd nanoflowers using the surfactant sodium N-(4-n-dodecyloxybenzoyl)-L-isoleucinate (SDBIL). The pH-dependent self-assembly using SDBIL is critical for nanoflower growth. The Pt and Pd nanoflowers show superior catalytic activity for Suzuki–Miyaura and Heck coupling reactions over spherical counterparts.

    18. Solid-State Structures

      Stable Oxoborate with Edge-Sharing BO4 Tetrahedra Synthesized under Ambient Pressure (pages 4967–4970)

      Shifeng Jin, Gemei Cai, Wanyan Wang, Meng He, Shunchong Wang and Xiaolong Chen

      Version of Record online: 10 JUN 2010 | DOI: 10.1002/anie.200907075

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      Back from the extreme: The formation of edge-sharing BO4 tetrahedra is excluded from borate structure chemistry and only rarely presents itself under extremely high pressure. Now this structure has been observed in an ambient pressure borate. Unlike high-pressure metastable phases, the title compound is stable up to its melting point. The tunnel structure of the compound is also accessible to mobile ions.

    19. Quantum Wires

      Synthesis of Ideal AM-6 and Elucidation of V4+-to-O Charge Transfer in Vanadate Quantum Wires (pages 4971–4975)

      Shuvo Jit Datta and Kyung Byung Yoon

      Version of Record online: 8 JUN 2010 | DOI: 10.1002/anie.200907088

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      Vanadosilicate zeolite AM-6, which contains a 3D array of vanadate (VIVO32−) quantum wires (see picture), was prepared as high-quality crystals (free from VV, titanosilicate seeds, and pore-blocking organic template cations) from inexpensive V2O5. The linear dependence of λmax and band-gap energy Eg on the partial charge on the framework O atoms reveal that the UV band of AM-6 is due to VIV-to-O metal-to-ligand charge transfer.

    20. Sustainable Chemistry

      Improving the Atom Efficiency of the Wittig Reaction by a “Waste as Catalyst/Co-catalyst” Strategy (pages 4976–4980)

      Jun-Jie Cao, Feng Zhou and Jian Zhou

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.201000896

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      Waste not want not: Reported is a strategy to improve the atom economy of the Wittig reaction by using it in tandem reactions that directly employ the waste Ph3PO as an in-situ-generated Lewis base catalyst/co-catalyst in the next step (see scheme).

    21. Nanostructures

      Monodisperse Yolk–Shell Nanoparticles with a Hierarchical Porous Structure for Delivery Vehicles and Nanoreactors (pages 4981–4985)

      Jian Liu, Shi Zhang Qiao, Sandy Budi Hartono and Gao Qing (Max) Lu

      Version of Record online: 28 MAY 2010 | DOI: 10.1002/anie.201001252

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      A good egg: A general and facile template strategy is presented for the fabrication of yolk–shell structures (see picture) with various types of movable cores, such as gold, SiO2, and magnetic Fe3O4. The vesicle template, formed of a fluorocarbon surfactant, is built up around the core.

    22. Extra-Large-Pore Zeolites

      The Synthesis of an Extra-Large-Pore Zeolite with Double Three-Ring Building Units and a Low Framework Density (pages 4986–4988)

      Jiuxing Jiang, Jose L. Jorda, Maria J. Diaz-Cabanas, Jihong Yu and Avelino Corma

      Version of Record online: 11 JUN 2010 | DOI: 10.1002/anie.201001506

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      The great wide open: High-throughput techniques have allowed an extra-large-pore zeolite to be obtained that has an 18×12×12 ring pore system. This material (see picture) has the lowest framework density for a silica-based fully-connected zeolite, and is the first example with double three-ring units in its framework.

    23. Metal Radical Complexes

      X-Ray Structures of Copper(II) and Nickel(II) Radical Salen Complexes: The Preference of Galactose Oxidase for Copper(II) (pages 4989–4992)

      Maylis Orio, Olivier Jarjayes, Hussein Kanso, Christian Philouze, Frank Neese and Fabrice Thomas

      Version of Record online: 23 APR 2010 | DOI: 10.1002/anie.201001040

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      Copper or nickel? The depicted CuII salen complex, an active-site model of galactose oxidase (GO), is a localized radical in the solid state with a quinoid distribution of bond lengths in one ring. While the ligand-radical structure is not metal-dependent, the composition of the radical SOMO is. This feature may explain the much lower reactivity of the Ni complex and nature's preference for a CuII center in GO.

    24. Synthetic Methods

      Straightforward Synthesis of Ethers: Metal-Free Reductive Coupling of Tosylhydrazones with Alcohols or Phenols (pages 4993–4996)

      José Barluenga, María Tomás-Gamasa, Fernando Aznar and Carlos Valdés

      Version of Record online: 2 JUN 2010 | DOI: 10.1002/anie.201001704

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      Ethers made easy: Heating a solution containing a tosylhydrazone and either a phenol or an alcohol in the presence of K2CO3 leads to the corresponding ethers (see scheme; MW=microwave, Ts=tosyl). The reaction is fairly general for the preparation of aryl alkyl and alkyl alkyl ethers, and represents a new method for the reductive etherification of carbonyl compounds.

    25. Organocatalysis

      The Elusive Enamine Intermediate in Proline-Catalyzed Aldol Reactions: NMR Detection, Formation Pathway, and Stabilization Trends (pages 4997–5003)

      Markus B. Schmid, Kirsten Zeitler and Ruth M. Gschwind

      Version of Record online: 8 JUN 2010 | DOI: 10.1002/anie.200906629

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      The missing link: The elusive enamine intermediate of nucleophilic proline catalysis was detected and stereochemically characterized by NMR analysis of the aldehyde self-aldolization reaction in dipolar aprotic solvents. NMR exchange spectroscopy (EXSY) was used to observe direct enamine formation from oxazolidinones. Additionally, the stabilization of the intermediate by the appropriate choice of solvent and substitution pattern on the aldehyde is presented.

    26. Oxidative Coupling

      Autoxidative Carbon–Carbon Bond Formation from Carbon–Hydrogen Bonds (pages 5004–5007)

      Áron Pintér, Abhishek Sud, Devarajulu Sureshkumar and Martin Klussmann

      Version of Record online: 11 JUN 2010 | DOI: 10.1002/anie.201000711

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      Only oxygen and acid! The oxidative coupling of xanthene and other activated benzylic compounds with carbon nucleophiles such as ketones, can be performed under ambient conditions without solvent by simply using oxygen and catalytic amounts of methanesulfonic acid. The proposed reaction mechanism involves substrate activation by formation of hydroperoxides; the method can therefore be regarded as an “autoxidative coupling reaction”.

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    4. Graphical Abstract
    5. News
    6. Book Reviews
    7. Highlight
    8. Essay
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    10. Communications
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