Angewandte Chemie International Edition

Cover image for Vol. 48 Issue 40

September 21, 2009

Volume 48, Issue 40

Pages 7267–7451

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Author Profile
    7. Book Review
    8. Highlights
    9. Review
    10. Communications
    11. Preview
    1. Cover Picture: Two-Dimensional Crystal Engineering: A Four-Component Architecture at a Liquid–Solid Interface (Angew. Chem. Int. Ed. 40/2009) (page 7267)

      Jinne Adisoejoso, Kazukuni Tahara, Satoshi Okuhata, Shengbin Lei, Yoshito Tobe and Steven De Feyter

      Article first published online: 17 SEP 2009 | DOI: 10.1002/anie.200990209

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      Four components self-assemble to form a supramolecular pattern physisorbed on atomically flat graphite, as described by S. De Feyter et al. in their Communication on page 7353 ff. Mixing fixed amounts of the four components in a common solvent and subsequent dropcasting leads to the exclusive formation of Kagomé lattices that are filled by site-specific template molecules, as revealed by scanning tunneling microscopy at the liquid–solid interface.

  2. Inside Cover

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Author Profile
    7. Book Review
    8. Highlights
    9. Review
    10. Communications
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    1. Inside Cover: Switching the Chirality of the Metal Environment Alters the Coordination Mode in Designed Peptides (Angew. Chem. Int. Ed. 40/2009) (page 7268)

      Anna F. A. Peacock, Jeanne A. Stuckey and Vincent L. Pecoraro

      Article first published online: 17 SEP 2009 | DOI: 10.1002/anie.200990210

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      As switching railway points alter the course of an approaching train, switching the chirality of a single residue in the interior of a de novo designed three-stranded coiled coil dramatically alters the metal-binding capability of the peptide and the resulting position and coordination environment of the metal ion. The Communication by Pecoraro et al. on page 7371 ff. explores the binding of CdII to the L and D enantiomers of thiol-containing penicillamine through spectroscopic studies in solution and X-ray crystallography.

  3. Graphical Abstract

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

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

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Author Profile
    7. Book Review
    8. Highlights
    9. Review
    10. Communications
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    1. Hans-Jörg Himmel (page 7288)

      Article first published online: 2 SEP 2009 | DOI: 10.1002/anie.200904211

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      “The biggest challenge facing scientists is that every answer creates at least two new questions. My favorite subject at school was history‥ …” This and more about Hans-Jörg Himmel can be found on page 7288.

  6. Book Review

    1. Top of page
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    7. Book Review
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    1. Metallic Nanomaterials.Nanomaterials for the Life Sciences, Volume 1. Edited by Challa S. S. R. Kumar. (page 7289)

      Ralph A. Sperling

      Article first published online: 17 SEP 2009 | DOI: 10.1002/anie.200903699

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      Wiley-VCH, Weinheim 2008. 571 pp., hardcover € 149.00.—ISBN 978-3527321513

  7. Highlights

    1. Top of page
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    7. Book Review
    8. Highlights
    9. Review
    10. Communications
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    1. Fluorescent Probes

      Über-Responsive Peptide-Based Sensors of Signaling Proteins (pages 7290–7292)

      Vyas Sharma and David S. Lawrence

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200903717

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      To GFP and beyond: Green fluorescent protein and its array of wavelength variants have transformed cell biology. However, the next generation of fluorescent probes (FL) may emerge from the chemistry laboratory. Sensors have been described that display huge fluorescent changes upon binding to their protein targets (see picture). Nevertheless, a number of challenges must be overcome before these species find universal application in cells and beyond.

    2. DNA Repair

      Once Overlooked, Now Made Visible: ATL Proteins and DNA Repair (pages 7293–7295)

      Thomas Reißner, Stephanie Schorr and Thomas Carell

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200904042

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      Damage report: Alkyltransferase-like proteins (ATLs) flip DNA lesions out of the DNA duplex but have no catalytic function. They act as recognition proteins that mark DNA lesions and allow repair (see picture; NER=nucleotide excision repair).

  8. Review

    1. Top of page
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    4. Graphical Abstract
    5. News
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    7. Book Review
    8. Highlights
    9. Review
    10. Communications
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    1. Supramolecular Surface Chemistry

      Molecular and Supramolecular Networks on Surfaces: From Two-Dimensional Crystal Engineering to Reactivity (pages 7298–7332)

      Johannes A. A. W. Elemans, Shengbin Lei and Steven De Feyter

      Article first published online: 11 SEP 2009 | DOI: 10.1002/anie.200806339

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      Seeing is believing: Scanning tunneling microscopy (STM) allows the visualization of molecules in real space on atomically flat conductive substrates (see picture), and has formed the basis for the rapid development of supramolecular chemistry at surfaces. This Review highlights recent developments in the design and functionality of supramolecular surface patterns, with a focus on chirality, porosity, and reactivity.

  9. Communications

    1. Top of page
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    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Author Profile
    7. Book Review
    8. Highlights
    9. Review
    10. Communications
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    1. Biosensors

      Immediate Detection of Living Bacteria at Ultralow Concentrations Using a Carbon Nanotube Based Potentiometric Aptasensor (pages 7334–7337)

      Gustavo A. Zelada-Guillén, Jordi Riu, Ali Düzgün and F. Xavier Rius

      Article first published online: 30 JUN 2009 | DOI: 10.1002/anie.200902090

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      Keeping the doctor away: An aptamer attached to an electrode coated with single-walled carbon nanotubes interacts selectively with bacteria (see picture). The resulting electrochemical response is highly accurate and reproducible and starts at ultralow bacteria concentrations, thus providing a simple, selective method for pathogen detection.

    2. Organocatalysis

      Trends in Organocatalytic Conjugate Addition to Enones: An Efficient Approach to Optically Active Alkynyl, Alkenyl, and Ketone Products (pages 7338–7342)

      Márcio Weber Paixão, Nicole Holub, Carlos Vila, Martin Nielsen and Karl Anker Jørgensen

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200903790

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      Three in one: Applying an organocatalytic tandem strategy to build a library of optically active alkynyl, alkenyl, and ketone products, starting from cyclic enones and β-keto sulfones, is shown to be rapid and efficient (see scheme; R=aryl, R′=H or alkyl).

    3. Cage Compounds

      Construction of Heterometallic Cages with Tripodal Metalloligands (pages 7343–7345)

      Hua-Bin Wu and Quan-Ming Wang

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200903575

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      Changing cages: The coordination preferences of the incorporated metals dictates the geometry of the heterometallic cages that are assembled by using AlL3 (HL=1-(4-pyridyl)butane-1,3-dione) as a metalloligand. A trigonal bipyramid and a giant capped octahedron (see picture; green Al, red O, blue N, purple Pd) were isolated. The unprecedented spontaneous resolution of the chiral trigonal bipyramidal complex M2M′3L6 with D3 symmetry was observed.

    4. Imaging Probes

      Imparting Multivalency to a Bifunctional Chelator: A Scaffold Design for Targeted PET Imaging Probes (pages 7346–7349)

      Wei Liu, Guiyang Hao, Michael A. Long, Tiffani Anthony, Jer-Tsong Hsieh and Xiankai Sun

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200903556

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      Two are better than one: Multivalent scaffolds for targeted PET imaging probes not only feature chelators that form stable and neutral complexes with a radiometal but also contain functional groups for presentation of multiple targeting molecules. A bivalent scaffold was synthesized and coupled with a targeting ligand to afford the probe, which was used to efficiently image tumors in vivo (see picture).

    5. Biomolecule Detection

      Multiplex Label-Free Detection of Biomolecules with an Imprinted Suspension Array (pages 7350–7352)

      Yuan-Jin Zhao, Xiang-Wei Zhao, Jing Hu, Juan Li, Wen-Yu Xu and Zhong-Ze Gu

      Article first published online: 3 SEP 2009 | DOI: 10.1002/anie.200903472

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      Appearing in print: Polymer beads with a photonic crystal structure can be prepared that display the molecular imprint of a label-free biomolecule to be analyzed. A series of beads corresponding to a series of analytes could be used for multiplex detection of biomolecules with remarkable sensitivity and specificity (see picture).

    6. Supramolecular Chemistry

      Two-Dimensional Crystal Engineering: A Four-Component Architecture at a Liquid–Solid Interface (pages 7353–7357)

      Jinne Adisoejoso, Kazukuni Tahara, Satoshi Okuhata, Shengbin Lei, Yoshito Tobe and Steven De Feyter

      Article first published online: 16 JUN 2009 | DOI: 10.1002/anie.200900436

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      Get it together: A four-component 2D crystal has been formed at a liquid–solid interface and successfully visualized by scanning tunneling microscopy. Simply premixing the four components and applying the solution onto the graphite surface leads to the spontaneous self-assembly of the 2D crystal. Selected guest molecules induce a structural transformation of the host network from nonporous to porous by coadsorption inside the formed pores.

    7. Magnetic Nanoparticles

      Unusual Magnetic Properties of Size-Controlled Iron Oxide Nanoparticles Grown in a Nanoporous Matrix with Tunable Pores (pages 7358–7361)

      Sher Alam, Chokkalingam Anand, Katsuhiko Ariga, Toshiyuki Mori and Ajayan Vinu

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200901570

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      Fully loaded: A facile nanosieve approach for the preparation of Fe2O3 nanoparticles that have uniform and tunable sizes and are highly dispersed over a mesoporous support is achieved by the simple adjustment of the pore diameter of the template matrix (see picture). The nanoparticles are very small (6.5–9.0 nm) and show superior magnetic properties compared to pure Fe2O3 nanoparticles prepared without using a support.

    8. DNA Hybridization

      A Light-Driven Supramolecular Optical Switch (pages 7362–7365)

      Shin-nosuke Uno, Chikara Dohno, Holger Bittermann, Vladimir L. Malinovskii, Robert Häner and Kazuhiko Nakatani

      Article first published online: 2 SEP 2009 | DOI: 10.1002/anie.200903251

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      Switched on: The fluorescence emission of a DNA-based optical switch can be reversibly switched from blue to green using modulating light of different wavelengths (see picture). The device is based on the hybridization of two pyrene-functionalized DNA strands in the presence of a photochromic azobenzene-containing effector ligand. Hybridization occurs only with the cis-configured ligand, and results in pyrene excimer fluorescence.

    9. Silicon Nanowires

      Directionally Integrated VLS Nanowire Growth in a Local Temperature Gradient (pages 7366–7370)

      Geunhee Lee, Yun Sung Woo, Jee-Eun Yang, Donghun Lee, Cheol-Joo Kim and Moon-Ho Jo

      Article first published online: 2 SEP 2009 | DOI: 10.1002/anie.200902451

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      Going straight: A simple and robust mechanism coherently directs nanowire growth directions by introducing a local temperature gradient as the local kinetic variable during the conventional vapor–liquid–solid (VLS) growth (see picture, scale bar=200 μm). The nanowires grow straight in the vertical direction, but possess kinks near the catalytic tips.

    10. Protein Design

      Switching the Chirality of the Metal Environment Alters the Coordination Mode in Designed Peptides (pages 7371–7374)

      Anna F. A. Peacock, Jeanne A. Stuckey and Vincent L. Pecoraro

      Article first published online: 3 JUL 2009 | DOI: 10.1002/anie.200902166

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      Outsiders make their presence felt: When the chirality of a single layer of amino acids was switched in a three-stranded coiled coil (see picture), X-ray crystallography revealed minimal perturbation of the α-helical backbone of the designed structure. In contrast, spectroscopic studies of cadmium binding showed that this switch in chirality dramatically altered the coordination environment and the position of binding.

    11. Amine Exchange

      Selective Amine Cross-Coupling Using Iridium-Catalyzed “Borrowing Hydrogen” Methodology (pages 7375–7378)

      Ourida Saidi, A. John Blacker, Mohamed M. Farah, Stephen P. Marsden and Jonathan M. J. Williams

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200904028

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      Something borrowed: Amine cross-coupling reactions are catalyzed using [{Cp*IrI2}2] (Cp*=C5Me5) in the absence of a base. A range of anilines were converted into their N-isopropyl derivatives, and the same process was also effective for alkylation of benzylamines and other aliphatic primary amines.

    12. Surface Processes

      Electron Transport in the Long-Range Charge-Recombination Dynamics of Single Encapsulated Dye Molecules on TiO2 Nanoparticle Films (pages 7379–7382)

      Xiangyang Wu, Toby D. M. Bell and Edwin K. L. Yeow

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200902596

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      Hitching a slow ride: Long-lived dark charge-separated states arise from the transport of the injected electron on TiO2 nanoparticles after it is transferred from single Atto647N dye molecules encapsulated in cucurbit[7]uril (CB7). These states are directly probed using the intermittency of the emission intensity trajectories (see spectra).

    13. Dioxygen Activation

      Solid-State Chemistry at an Isolated Copper(I) Center with O2 (pages 7383–7386)

      Grégory Thiabaud, Geoffroy Guillemot, Isabelle Schmitz-Afonso, Benoit Colasson and Olivia Reinaud

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200902691

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      A solid performer: Chemo- and regioselective oxygenation of an organic moiety with O2 in the solid state gives a CuI complex and a four-electron oxidized compound as final products (see scheme). A single CuI center in interaction with O2 mediates an even-electron transfer process without the assistance of a redox cofactor and provides further support for a [CuO2]+ core as a reactive species allowing C[BOND]H bond cleavage.

    14. Asymmetric Catalysis

      Chiral Guanidinium Salt Catalyzed Enantioselective Phospha-Mannich Reactions (pages 7387–7390)

      Xiao Fu, Wei-Tian Loh, Yan Zhang, Tao Chen, Ting Ma, Hongjun Liu, Jianmin Wang and Choon-Hong Tan

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200903971

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      Zero, one, or two? Guanidinium catalyst 1⋅HBArF4 (ArF=3,5-(CF3)2C6H3, Bn=benzyl, Ts=4-toluenesulfonyl) was obtained in a single step from a commercially available diamine. By using this catalyst an asymmetric phospha-Mannich reaction has been developed, involving secondary phosphine oxides and H-phosphinates as the P nucleophile. A series of enantiomerically enriched α-amino phosphine oxides (2), α-amino phosphinate, and H-phosphinates containing a P-chiral center were prepared.

    15. Cooperative Catalysis

      Plagiarizing Proteins: Enhancing Efficiency in Asymmetric Hydrogen-Bonding Catalysis through Positive Cooperativity (pages 7391–7394)

      Christopher R. Jones, G. Dan Pantoş, Angus J. Morrison and Martin D. Smith

      Article first published online: 2 SEP 2009 | DOI: 10.1002/anie.200903063

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      A new twist for a fold: Conformationally well-defined thiourea catalysts, like that shown, stabilized by intramolecular hydrogen bonds demonstrate cooperative ligand–receptor binding. This conformation leads to significantly enhanced catalytic efficiency, resulting in higher turnover rates and lower catalyst loading whilst maintaining high enantioselectivity in a model reaction.

    16. Surface Derivatization

      Patterning of Surfaces by Oxidation of Amine-Containing Compounds Using Scanning Electrochemical Microscopy (pages 7395–7397)

      Charles Cougnon, Janine Mauzeroll and Daniel Bélanger

      Article first published online: 27 AUG 2009 | DOI: 10.1002/anie.200903092

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      A micropatterning procedure based on the oxidation of an amine starts with the reduction of a nitro-containing compound at the scanning electrochemical microscope tip (see picture). After diffusion in the interelectrode gap, the amine is oxidized on a gold sample, thus resulting in a local derivatization. This procedure is expected to be suitable for extended microstructuring of surfaces.

    17. Homogeneous Catalysis

      Room-Temperature Copper-Catalyzed Carbon–Nitrogen Coupling of Aryl Iodides and Bromides Promoted by Organic Ionic Bases (pages 7398–7401)

      Chu-Ting Yang, Yao Fu, Yao-Bing Huang, Jun Yi, Qing-Xiang Guo and Lei Liu

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200903158

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      Good solubility alone does not explain the performance of organic ionic bases in the room-temperature coupling of aryl iodides and even bromides with aliphatic and aromatic amines and N-heterocycles (NuH; see scheme). Conductivity measurements show that these organic ionic bases, which contain tetraalkylammonium or -phosphonium cations, are readily ionized in organic solvents.

    18. Natural Product Synthesis

      Enantioselective Total Synthesis of the Marine Toxin (−)-Gymnodimine Employing a Barbier-Type Macrocyclization (pages 7402–7405)

      Ke Kong, Daniel Romo and Changsuk Lee

      Article first published online: 2 SEP 2009 | DOI: 10.1002/anie.200903432

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      Sea the synthesis: At ambient temperature, tert-butyllithium promotes a Barbier-type macrocyclization in the first total synthesis of (−)-gymnodimine (Ts: toluene-4-sulfonyl; TBS: tert-butyldimethylsilyl), a member of the spirocyclic-imine family of marine toxins. The synthesis also features a vinylogous Mukaiyama aldol process to couple the labile butenolide moiety onto a macrocyclic ketone intermediate.

    19. Metal–Metal Interactions

      Amidinato– and Guanidinato–Cobalt(I) Complexes: Characterization of Exceptionally Short Co–Co Interactions (pages 7406–7410)

      Cameron Jones, Christian Schulten, Richard P. Rose, Andreas Stasch, Simon Aldridge, William D. Woodul, Keith S. Murray, Boujemaa Moubaraki, Marcin Brynda, Giovanni La Macchia and Laura Gagliardi

      Article first published online: 31 AUG 2009 | DOI: 10.1002/anie.200900780

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      CoCo loco! Ligand-bridged dimers (see picture) with the shortest known Co–Co interactions are the first amidinato and guanidinato cobalt(I) complexes. The nature of the interactions has been probed by magnetic and theoretical investigations, and has been shown to be multiconfigurational. Preliminary reactivity studies of the complexes have also been carried out.

    20. Amide Activation

      Fmoc Solid-Phase Synthesis of C-Terminal Peptide Thioesters by Formation of a Backbone Pyroglutamyl Imide Moiety (pages 7411–7414)

      A. Pernille Tofteng, Kasper K. Sørensen, Kilian W. Conde-Frieboes, Thomas Hoeg-Jensen and Knud J. Jensen

      Article first published online: 3 SEP 2009 | DOI: 10.1002/anie.200903710

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      Activating an inactive bond: A new concept in synthetic peptide chemistry, backbone amide activation, proceeds through the selective conversion of a backbone amide into an imide, followed by nucleophilic acyl displacement (see scheme; Boc=tert-butoxycarbonyl, Pg=protecting group). This methodology represents a new approach to solid-phase synthesis of C-terminal peptide thioesters, and may become a general tool for the synthesis of peptide thioesters.

    21. Dinitrogen Cleavage

      Titanium-Promoted Dinitrogen Cleavage, Partial Hydrogenation, and Silylation (pages 7415–7419)

      Grigory B. Nikiforov, Indu Vidyaratne, Sandro Gambarotta and Ilia Korobkov

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200903648

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      Breaking up: Reduction of a trivalent titanium complex afforded N[BOND]N cleavage with formation of TiIV nitride complexes (see structure), which can be converted into silylated derivatives.

    22. Enantioselectivity

      Reversal of Enantioselectivity between the Copper(I)- and Silver(I)-Catalyzed 1,3-Dipolar Cycloaddition Reactions Using a Brucine-Derived Amino Alcohol Ligand (pages 7420–7423)

      Hun Young Kim, Hui-Ju Shih, William E. Knabe and Kyungsoo Oh

      Article first published online: 2 SEP 2009 | DOI: 10.1002/anie.200903479

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      The old switcheroo: The switch in the enantioselectivity of a reaction by using a single chiral source has been achieved using different metal binding modes of the chiral amino alcohol 1 in the presence of CuI and AgI sources. Azomethine ylides were shown to undergo highly enantio- and diastereoselective 1,3-dipolar cycloadditions with substituted tert-butyl acrylates to provide both of the enantiomerically enriched pyrrolidines (see scheme).

    23. MOF-Based Catalysts

      Engineering a Metal–Organic Framework Catalyst by Using Postsynthetic Modification (pages 7424–7427)

      Kristine K. Tanabe and Seth M. Cohen

      Article first published online: 1 SEP 2009 | DOI: 10.1002/anie.200903433

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      MOF+PSM=Cat: A highly porous metal–organic framework (MOF) is metalated and transformed into an active, robust, reusable catalyst (Cat.) using postsynthetic modification (PSM).

    24. Asymmetric Catalysis

      Asymmetric Construction of Polycyclic Indoles through Olefin Cross-Metathesis/Intramolecular Friedel–Crafts Alkylation under Sequential Catalysis (pages 7428–7431)

      Quan Cai, Zhuo-An Zhao and Shu-Li You

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200903462

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      A synthetic shortcut: A highly efficient cascade reaction (see scheme) led to polycyclic indoles with excellent enantioselectivity. The combination of the two steps through sequential catalysis enables the use of more readily available starting materials and makes the synthesis more practical. Boc=tert-butoxycarbonyl.

    25. Highly Enantioselective Epoxidation of Styrenes Catalyzed by Proline-Derived C1-Symmetric Titanium(Salan) Complexes (pages 7432–7435)

      Kazuhiro Matsumoto, Takuya Oguma and Tsutomu Katsuki

      Article first published online: 31 AUG 2009 | DOI: 10.1002/anie.200903567

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      Titanium tough! Novel proline-derived C1-symmetric titanium(salan) complexes have been used to catalyze the epoxidation of styrene derivatives with aqueous hydrogen peroxide as the oxidant (see scheme). High enantiomeric excesses ranging from 96 to 98 % were obtained.

    26. Cross-Coupling

      Palladium-Catalyzed Cross-Coupling of Aryl Halides Using Organotitanium Nucleophiles (pages 7436–7439)

      Hang Wai Lee, Fuk Loi Lam, Chau Ming So, Chak Po Lau, Albert S. C. Chan and Fuk Yee Kwong

      Article first published online: 3 SEP 2009 | DOI: 10.1002/anie.200904033

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      They make a good couple: Catalysts generated from Pd(OAc)2 and indolylphosphine ligands are highly effective in the titanium-mediated coupling of aryl halides. Catalyst loadings as low as 0.05 mol % Pd can be used. The mild reaction conditions also allow the coupling of aryl sulfonyl chlorides with aryl titanium reagents to generate diaryl sulfones.

    27. Molecular Recognition

      A Pyridinium–Barbiturate–Betaine Dye with Pronounced Negative Solvatochromism: A New Approach for Molecular Recognition (pages 7440–7443)

      Ina Bolz, Dieter Schaarschmidt, Tobias Rüffer, Heinrich Lang and Stefan Spange

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200902860

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      World record: The betaine dye 1 exhibits the highest negative solvatochromic range yet seen. Because of its pronounced push–pull system, 1 is suitable for the detection of polarity changes, acid–base reactions, and the formation of complexes with complementary hydrogen-bond sequences, which can even be followed by the naked eye.

    28. Halonium Ions

      Bissilylated Halonium Ions: [Me3Si[BOND]X[BOND]SiMe3][B(C6F5)4] (X=F, Cl, Br, I) (pages 7444–7447)

      Mathias Lehmann, Axel Schulz and Alexander Villinger

      Article first published online: 8 SEP 2009 | DOI: 10.1002/anie.200902992

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      Double duty: The series of salts containing the bissilylated halonium cation [Me3Si[BOND]X[BOND]SiMe3]+ (X=F, Cl, Br, and I; see picture) has been generated and fully characterized in the super Lewis acidic silylating medium Me3Si[BOND]X (as solvent and reactant) and [Me3Si][B(C6F5)4] (as silylating reagent).

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