Angewandte Chemie International Edition

Cover image for Angewandte Chemie International Edition

March 30, 2009

Volume 48, Issue 15

Pages 2615–2805

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Cover Picture: Compartmentalization of Chemically Separated Components into Droplets (Angew. Chem. Int. Ed. 15/2009) (page 2615)

      J. Scott Edgar, Graham Milne, Yiqiong Zhao, Chaitanya P. Pabbati, David S. W. Lim and Daniel T. Chiu

      Article first published online: 24 MAR 2009 | DOI: 10.1002/anie.200990072

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      Electroosmotic-flow-driven droplet generation integrated with capillary electrophoresis (CE) allows the molecular components separated by CE to be compartmentalized into a stream of droplets, as reported by D. T. Chiu and co-workers in their Communication on page 2719 ff. and illustrated on the cover picture. After separation and droplet compartmentalization, the droplet-confined bands either can be docked and studied on-chip or removed off-chip for a second-dimension separation and further analysis.

  2. Inside Cover

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Inside Cover: Artificial Ribozyme Switches Containing Natural Riboswitch Aptamer Domains (Angew. Chem. Int. Ed. 15/2009) (page 2616)

      Markus Wieland, Armin Benz, Benedikt Klauser and Jörg S. Hartig

      Article first published online: 24 MAR 2009 | DOI: 10.1002/anie.200990073

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      Fusions of a ribozyme and an aptamer of a natural riboswitch (thiamine pyrophosphate, TPP) are used to construct artificial thiamine-dependent switches of gene expression. As J. S. Hartig et al. describe in their Communication on page 2715 ff., insertion of these RNA elements into bacterial mRNAs allows translation of the message to be switched on or off. TPP triggers changes to the ribozyme-mediated mRNA cleavage, resulting in liberation of the message for translational initiation.

  3. Graphical Abstract

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Graphical Abstract: Angew. Chem. Int. Ed. 15/2009 (pages 2619–2630)

      Article first published online: 24 MAR 2009 | DOI: 10.1002/anie.200990074

  4. Corrigendum

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

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

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. K. Suzuki (page 2635)

      Article first published online: 24 MAR 2009 | DOI: 10.1002/anie.200900104

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      “My first experiment was preparation of proline-derived chiral ligands for asymmetric alkylation. My favorite subjects at school were history and English….” This and more about Keisuke Suzuki can be found on page 2635.

  7. Book Reviews

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

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Coordination Chemistry

      Is Cyanide Really a Strong-Field Ligand? (pages 2638–2640)

      Mikio Nakamura

      Article first published online: 16 FEB 2009 | DOI: 10.1002/anie.200805446

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      Iron man or weakling? Ligand-field strengths are conveniently expressed by the empirical spectrochemical series. Although cyanide has been deeply entrenched as a strong-field ligand, a couple of recent examples cast doubt toward the position of this ligand, namely the high-spin (S=2) states of [CrII(CN)5]3− and [FeII(tpp)(CN)]. tpp=meso-tetraphenylporphinate.

    2. Transition-Metal Complexes

      Dynamic Crystals: Visually Detected Mechanochemical Changes in the Luminescence of Gold and Other Transition-Metal Complexes (pages 2641–2644)

      Alan L. Balch

      Article first published online: 16 FEB 2009 | DOI: 10.1002/anie.200805602

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      Back to the grindstone: Certain crystalline complexes of gold, platinum, and vanadium undergo dramatic changes in their luminescence or their color upon grinding. The picture shows the transformation of colorless crystals of [(F5C6Au)2(μ-1,4-CN2C6H4)] powder from a blue-emitting form (λmax=415 nm) to a yellow/green-emitting form (λmax=533 nm) on grinding with a pestle. The process is reversible.

    3. Ionic Interactions

      From Ionic Liquids to Supramolecular Polymers (pages 2645–2647)

      Stephen L. Craig

      Article first published online: 16 FEB 2009 | DOI: 10.1002/anie.200805603

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      Charging forward: Ionic interactions presented in a multivalent fashion in small-molecule ionic liquids lead to functional polymer-like materials (see picture) that are consistent with the formation of a supramolecular ionic network. For example, the ionic material formed from a dication consisting of two covalently linked tetraalkyl phosphonium moieties and a porphyrin tetracarboxylate has a viscosity of 106 Pa s at 25 °C.

  9. Essay

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Homochirality

      “If Pigs Could Fly” Chemistry: A Tutorial on the Principle of Microscopic Reversibility (pages 2648–2654)

      Donna G. Blackmond

      Article first published online: 30 DEC 2008 | DOI: 10.1002/anie.200804566

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      Through a glass darkly: Several recent autocatalytic reaction models for the origin of homochirality have suggested ways in which one enantiomer of the product might be reconverted into the other by a recycling reaction in a closed system. These models are revealed to violate the principle of microscopic reversibility, a powerful tool for assessing the plausibility of proposed reaction networks even at far-from-equilibrium conditions.

  10. Minireview

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Cross-Coupling

      Secondary Alkyl Halides in Transition-Metal-Catalyzed Cross-Coupling Reactions (pages 2656–2670)

      Alena Rudolph and Mark Lautens

      Article first published online: 28 JAN 2009 | DOI: 10.1002/anie.200803611

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      Secondary, but second to none: The use of secondary alkyl halides in transition-metal-catalyzed cross-coupling reactions (see scheme) has advanced significantly over the last five years. Selected examples of these transformations are examined, including mechanistic and stereochemical aspects.

  11. Review

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Aptamers

      The Chemical Biology of Aptamers (pages 2672–2689)

      Günter Mayer

      Article first published online: 24 MAR 2009 | DOI: 10.1002/anie.200804643

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      Taking a strand: Aptamers are small single-stranded oligonucleotides that fold into a well-defined 3D structure and interact with high affinity and specificity with their target molecules, thereby inhibiting their biological functions. Aptamers can be synthesized by either chemical and/or enzymatic procedures and can thus be considered as both chemical and biological substances. The current status and new developments in this area are described.

  12. Communications

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Reviews
    9. Highlights
    10. Essay
    11. Minireview
    12. Review
    13. Communications
    14. Preview
    1. Molecules in Outer Space

      Raman Spectroscopic Study of the Phase Transition of Amorphous to Crystalline β-Carbonic Acid (pages 2690–2694)

      Ingrid Kohl, Katrin Winkel, Marion Bauer, Klaus R. Liedl, Thomas Loerting and Erwin Mayer

      Article first published online: 11 FEB 2009 | DOI: 10.1002/anie.200805300

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      What's the matter? The laboratory Raman spectra for carbonic acid (H2CO3), both for the β-polymorph and its amorphous state, are required to detect carbonic acid on the surface of the pole caps of Mars in 2009, when the Mars Microbeam Raman Spectrometer lands on the planet. The picture shows a martian crater with ice of unknown composition, possibly containing carbonic acid (image adapted from DLR, with permission from ESA, DLR, and FU Berlin –-G. Neukum).

    2. Graft Polycondensation

      Grafting of Polyfluorene by Surface-Initiated Suzuki Polycondensation (pages 2695–2698)

      Tetyana Beryozkina, Ksenia Boyko, Natalya Khanduyeva, Volodymyr Senkovskyy, Marta Horecha, Ulrich Oertel, Frank Simon, Manfred Stamm and Anton Kiriy

      Article first published online: 4 MAR 2009 | DOI: 10.1002/anie.200806217

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      Graft work: The first surface-initiated and site-specific palladium-catalyzed Suzuki polycondensation that allows selective grafting and patterning of semiconducting and emissive poly[9,9-bis(2-ethylhexyl)fluorene] (1) at room temperature is developed (see scheme). The pattering is demonstrated by AFM (see image).

    3. Organocatalysis

      5-(Pyrrolidin-2-yl)tetrazole-Catalyzed Aldol and Mannich Reactions: Acceleration and Lower Catalyst Loading in a Continuous-Flow Reactor (pages 2699–2702)

      Arjan Odedra and Peter H. Seeberger

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200804407

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      Continuous organocatalysis: Fast aldol and Mannich reactions require less catalyst when conducted in a microreactor. A proline tetrazole derivative (5–10 mol %) catalyzes asymmetric aldol reactions between various aromatic aldehydes and ketones in microreactor at 60 °C with reaction times ranging from 10 to 30 min.

    4. Photonic Crystals

      Electrodeposition of 3D Ordered Macroporous Germanium from Ionic Liquids: A Feasible Method to Make Photonic Crystals with a High Dielectric Constant (pages 2703–2707)

      Xiangdong Meng, Rihab Al-Salman, Jiupeng Zhao, Natalia Borissenko, Yao Li and Frank Endres

      Article first published online: 6 MAR 2009 | DOI: 10.1002/anie.200805252

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      A promising method for the production of germanium photonic crystals consists of electrodeposition of Ge from GeCl4-containing ionic liquids inside templates of polystyrene colloidal crystals and subsequent removal of the template. This room-temperature method gives rise to the fabrication of a three-dimensional highly ordered macroporous germanium nanostructure (see picture; scale: 2 μm) as a prototype of a photonic crystal.

    5. Asymmetric Catalysis

      Asymmetric Suzuki–Miyaura Coupling in Water with a Chiral Palladium Catalyst Supported on an Amphiphilic Resin (pages 2708–2710)

      Yasuhiro Uozumi, Yutaka Matsuura, Takayasu Arakawa and Yoichi M. A. Yamada

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200900469

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      You oughta use water: Broad functional-group (FG) tolerance was observed for the title coupling of aryl halides (X=Cl, Br, I) and aryl boronic acids to give biaryl compounds with up to 94 % ee. The chiral imidazoindole phosphine–palladium catalyst supported on an amphiphilic polystyrene–poly(ethylene glycol) (PS–PEG) resin could be recycled readily.

    6. Time-Resolved EXAFS

      Structural Determination of a Photochemically Active Diplatinum Molecule by Time-Resolved EXAFS Spectroscopy (pages 2711–2714)

      Renske M. van der Veen, Chris J. Milne, Amal El Nahhas, Frederico A. Lima, Van-Thai Pham, Jonathan Best, Julia A. Weinstein, Camelia N. Borca, Rafael Abela, Christian Bressler and Majed Chergui

      Article first published online: 5 MAR 2009 | DOI: 10.1002/anie.200805946

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      Metallica: A large contraction of the Pt[BOND]Pt bond in the triplet excited state of the photoreactive [Pt2(P2O5H2)4]4− ion is determined by time-resolved X-ray absorption spectroscopy (see picture). The strengthening of the Pt[BOND]Pt interaction is accompanied by a weakening of the ligand coordination bonds, resulting in an elongation of the platinum–ligand bond that is determined for the first time.

    7. RNA Technologies

      Artificial Ribozyme Switches Containing Natural Riboswitch Aptamer Domains (pages 2715–2718)

      Markus Wieland, Armin Benz, Benedikt Klauser and Jörg S. Hartig

      Article first published online: 20 JAN 2009 | DOI: 10.1002/anie.200805311

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      RNA Lego: The use of natural riboswitch aptamers in synthetic RNA switches (see picture) should broaden the scope of artificial RNA regulators dramatically. It is shown that thiamine pyrophosphate (TPP) aptamers can be used in engineered devices as very sensitive switches of gene expression in unmodified organisms. The approach demonstrates that intrinsic metabolites can be utilized as external effectors of cellular functions.

    8. Separation Techniques

      Compartmentalization of Chemically Separated Components into Droplets (pages 2719–2722)

      J. Scott Edgar, Graham Milne, Yiqiong Zhao, Chaitanya P. Pabbati, David S. W. Lim and Daniel T. Chiu

      Article first published online: 13 JAN 2009 | DOI: 10.1002/anie.200805396

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      Not merely a drop in the ocean: The integration of capillary electrophoresis (CE) with droplet generation driven by electroosmotic flow enabled the compartimentalization of molecular components separated by CE in a series of droplets (see picture; the green bars represent the separated analytes). The droplet-confined bands can be docked and studied on a chip.

    9. Biosensors

      Interfacing Glycosylated Carbon-Nanotube-Network Devices with Living Cells to Detect Dynamic Secretion of Biomolecules (pages 2723–2726)

      Herry Gunadi Sudibya, Jimei Ma, Xiaochen Dong, Simon Ng, Lain-Jong Li, Xue-Wei Liu and Peng Chen

      Article first published online: 4 MAR 2009 | DOI: 10.1002/anie.200805514

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      A sense of cell-being: Single-walled carbon nanotubes (SWNTs) are functionalized with bioactive monosaccharides to enable their use as biosensors. The glycosylated nanotube network is biocompatible and can interface with living cells (see scheme) to electronically detect biomolecular release with high temporal resolution and high sensitivity.

    10. Nanomaterials

      Sonochemical Synthesis of Highly Luminescent Zinc Oxide Nanoparticles Doped with Magnesium(II) (pages 2727–2731)

      Huan-Ming Xiong, Dmitry G. Shchukin, Helmuth Möhwald, Yang Xu and Yong-Yao Xia

      Article first published online: 6 MAR 2009 | DOI: 10.1002/anie.200805590

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      A bright idea: Mg/ZnO nanoparticles that exhibit bright, stable photoluminescence both in colloidal dispersions and in the solid state are formed by doping MgII ions into ZnO nanoparticles by sonochemical synthesis. The changes in their band gaps and luminescence properties rely on the defect concentrations inside the ZnO nanoparticles; these concentrations are determined by the Mg/Zn molar ratios (see picture).

    11. Multidimensional NMR Spectroscopy

      Single-Scan 2D Hadamard NMR Spectroscopy (pages 2732–2736)

      Assaf Tal, Boaz Shapira and Lucio Frydman

      Article first published online: 5 MAR 2009 | DOI: 10.1002/anie.200805612

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      Scan and deliver: By combining imaging-based spectral/spatial 2D radiofrequency manipulations (see scheme, left) with Hadamard-weighting principles, 2D NMR spectra can be retrieved within a single scan (right). This approach can give homo- or heteronuclear correlations with an enhanced sensitivity over conventional ultrafast 2D NMR spectroscopy.

    12. Polyoxometalates

      Symmetry versus Minimal Pentagonal Adjacencies in Uranium-Based Polyoxometalate Fullerene Topologies (pages 2737–2740)

      Ginger E. Sigmon, Daniel K. Unruh, Jie Ling, Brittany Weaver, Matthew Ward, Laura Pressprich, Antonio Simonetti and Peter C. Burns

      Article first published online: 4 MAR 2009 | DOI: 10.1002/anie.200805870

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      C U soon: Clusters containing 60, 44, and 36 uranyl peroxide hydroxide polyhedra (see picture) adopt fullerene topologies of maximum symmetry. The largest of these, denoted U60, is topologically identical to C60 with no pentagonal adjacencies and the highest possible symmetry. U44 adopts the topology with maximum symmetry rather than that with the lowest number of pentagonal adjacencies.

    13. Polymer Dots

      Ratiometric Single-Nanoparticle Oxygen Sensors for Biological Imaging (pages 2741–2745)

      Changfeng Wu, Barbara Bull, Kenneth Christensen and Jason McNeill

      Article first published online: 27 FEB 2009 | DOI: 10.1002/anie.200805894

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      It makes sense: Conjugated polymer nanoparticles doped with a platinum porphyrin dye exhibit bright phosphorescence that is highly sensitive to the concentration of molecular oxygen. The small size, extraordinary brightness, excellent sensitivity, and ratiometric emission, together with the demonstration of single-particle sensing and cellular uptake, indicate the potential of the nanoparticle sensors for quantitative mapping of local molecular oxygen concentration.

    14. Transition States

      Dynamics of 1,3-Dipolar Cycloaddition Reactions of Diazonium Betaines to Acetylene and Ethylene: Bending Vibrations Facilitate Reaction (pages 2746–2748)

      Lai Xu, Charles E. Doubleday and K. N. Houk

      Article first published online: 20 FEB 2009 | DOI: 10.1002/anie.200805906

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      Getting the bends: The dynamics of 1,3-dipolar cycloaddition reactions have been explored by decomposing transition vector, quasi-classical trajectories, and single trajectories. Dipole bending (see picture) makes the largest contribution to the TS distortion energy and constitutes the major part of transition-state distortion energy in the favored concerted pathway.

    15. DNA Structures

      Self-Assembly of a Four-Helix Bundle on a DNA Quadruplex (pages 2749–2751)

      Brooke A. Rosenzweig and Andrew D. Hamilton

      Article first published online: 6 MAR 2009 | DOI: 10.1002/anie.200804849

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      Come together: A novel method for assembling monomers and controlling structure of a de novo helix bundle protein is described. A guanine (G)-rich oligodeoxynucleotide scaffold forms a hydrogen-bonded DNA quadruplex in the presence of potassium counterions, thereby inducing a helical structure and fourfold stoichiometry in conjugated, amphiphilic peptide sequences. The DNA scaffold shows potential for rapidly assembling designed proteins.

    16. Self-Assembly

      Micelle and Vesicle Formation of Amphiphilic Nanoparticles (pages 2752–2754)

      Marija S. Nikolic, Charlotta Olsson, Andrea Salcher, Andreas Kornowski, Anja Rank, Rolf Schubert, Andreas Frömsdorf, Horst Weller and Stephan Förster

      Article first published online: 27 FEB 2009 | DOI: 10.1002/anie.200805158

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      Nanoparticle brushes: Complex nanostructures can be formed by self assembly of amphiphilic CdSe/CdS core–shell nanoparticles that bear a brushlike layer of poly(ethylene oxide) chains. This route is based on controlling the volume fractions of hydrophilic and hydrophobic moieties within the particles and allows the formation of micellar, cylindrical, or vesicular nanoobjects (see picture).

    17. Bioelectronic Noses

      Polypyrrole Nanotubes Conjugated with Human Olfactory Receptors: High-Performance Transducers for FET-Type Bioelectronic Noses (pages 2755–2758)

      Hyeonseok Yoon, Sang Hun Lee, Oh Seok Kwon, Hyun Seok Song, Eun Hae Oh, Tai Hyun Park and Jyongsik Jang

      Article first published online: 9 MAR 2009 | DOI: 10.1002/anie.200805171

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      Get a whiff of this: Human olfactory receptor (hOR)-conjugated polypyrrole (PPy) nanotubes were integrated into the field-effect transistor (FET) sensor platform for the fabrication of high-performance bioelectronic noses (see picture, S=source, D=drain). The device can translate and amplify hOR–odorant interaction into a detectable signal, and it showed highly sensitive and specific responses toward a target odorant.

    18. Multifunctional Nanoparticles

      Gold Nanorod/Fe3O4 Nanoparticle “Nano-Pearl-Necklaces” for Simultaneous Targeting, Dual-Mode Imaging, and Photothermal Ablation of Cancer Cells (pages 2759–2763)

      Chungang Wang, Jiji Chen, Tom Talavage and Joseph Irudayaraj

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200805282

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      Gold and pearls: Multifunctional nanoparticles, each composed of a single, amine-modified gold nanorod, decorated with multiple “pearls” of Fe3O4 nanoparticles capped with carboxy groups, are prepared. Their effectiveness in simultaneous targeting, dual-mode imaging, and photothermal ablation of breast cancer cells is demonstrated.

    19. Biosensors

      A Detection System Based on Giant Magnetoresistive Sensors and High-Moment Magnetic Nanoparticles Demonstrates Zeptomole Sensitivity: Potential for Personalized Medicine (pages 2764–2767)

      Balasubramanian Srinivasan, Yuanpeng Li, Ying Jing, YunHao Xu, Xiaofeng Yao, Chengguo Xing and Jian-Ping Wang

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200806266

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      Zeptomole detector: A highly sensitive giant-magnetoresistive chip and FeCo nanoparticles can be used to linearly detect 600–4500 copies of streptavidin. Under unoptimized conditions, this system also detects human IL-6 with a sensitivity 13-times higher than that of standard ELISA techniques.

    20. Asymmetric Catalysis

      Unprecedented Selectivity via Electronic Substrate Recognition in the 1,4-Addition to Cyclic Olefins Using a Chiral Disulfoxide Rhodium Catalyst (pages 2768–2771)

      Justus J. Bürgi, Ronaldo Mariz, Michele Gatti, Emma Drinkel, Xinjun Luan, Sascha Blumentritt, Anthony Linden and Reto Dorta

      Article first published online: 3 MAR 2009 | DOI: 10.1002/anie.200900429

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      From zero to hero? Sulfoxides are generally not considered useful ligand entities in asymmetric metal catalysis. However, a chiral disulfoxide as a chelating ligand in the rhodium-catalyzed 1,4-addition of aryl boronic acids to cyclic, α,β-unsaturated ketones and esters gives impressive catalytic results, thus opening the door to future applications of this new chiral ligand class.

    21. Electronic Energy Transfer

      Exploring the Limits of Förster Theory for Energy Transfer at a Separation of 20 Å (pages 2772–2776)

      Raymond Ziessel, Mohammed A. H. Alamiry, Kristopher J. Elliott and Anthony Harriman

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200900188

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      Cutting the corner: An excellent agreement has been obtained between experimental and computed coulombic coupling matrix elements for donor–spacer–acceptor systems, which consist of a boron dipyrromethane donor and acceptor in various stages of protonation. This correlation occurs in spite of reservations about the validity of Förster theory being applied to intramolecular electronic energy transfer (ET) over short (e.g., 20 Å) distances (see picture).

    22. Synthetic Methods

      Synthesis of 1,3-Diamines Through Rhodium-Catalyzed C[BOND]H Insertion (pages 2777–2779)

      Toshiki Kurokawa, Mihyong Kim and J. Du Bois

      Article first published online: 6 MAR 2009 | DOI: 10.1002/anie.200806192

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      A grand opening: N-Boc-N-alkylsulfamides are effective substrates for the title transformation. Oxidative cyclization is highly chemoselective as well as being both stereospecific and diastereoselective. With the advent of new protocols that facilitate ring opening of the six-membered-ring heterocyclic products, access to differentially protected 1,3-diamines has been made possible (see scheme).

    23. Photocrystallography

      Photomagnetic Switching of the Complex [Nd(dmf)4(H2O)3(μ-CN)Fe(CN)5]⋅H2O Analyzed by Single-Crystal X-Ray Diffraction (pages 2780–2783)

      Helle Svendsen, Jacob Overgaard, Marie Chevallier, Eric Collet and Bo B. Iversen

      Article first published online: 6 MAR 2009 | DOI: 10.1002/anie.200805997

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      X-ray vision: Single-crystal XRD experiments (see picture) reveal the excited-state structure of the photomagnetic heterobimetallic title complex. The system shows a decrease in all the iron–ligand bond lengths, suggesting that photoexcitation involves a ligand-to-metal charge transfer or a change in the superexchange coupling between the metal centers.

    24. Heterogeneous Catalysis

      Direct Aerosol Synthesis of Large-Pore Amorphous Mesostructured Aluminosilicates with Superior Acid-Catalytic Properties (pages 2784–2787)

      Stéphanie Pega, Cédric Boissière, David Grosso, Thierry Azaïs, Alexandra Chaumonnot and Clément Sanchez

      Article first published online: 5 MAR 2009 | DOI: 10.1002/anie.200805217

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      An old dream comes true: A direct and environmentally benign synthetic strategy was developed for the aerosol-based mass production of large-pore mesostructured aluminosilicate powders (see TEM image). Although amorphous, some powders exhibit higher activity towards m-xylene isomerization and lower coke formation than a Y-zeolite based industrial reference catalyst.

    25. Tandem Cyclization

      Palladium-Catalyzed Three-Component Cascade Cyclization Reaction of Bisallenes with Propargylic Carbonates and Organoboronic Acids: Efficient Construction of cis-Fused Bicyclo[4.3.0]nonenes (pages 2788–2791)

      Wei Shu, Guochen Jia and Shengming Ma

      Article first published online: 11 MAR 2009 | DOI: 10.1002/anie.200805422

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      A bicycle built for two: The title reaction affords cis-fused bicyclo[4.3.0]nonenes from readily available 1,5-bisallenes with structurally diverse propargylic carbonates and arylboronic acids (see scheme; X=NTs, C(E1)2 with E1=CO2Bn, SO2Ph, dba=trans,trans-dibenzylidenacetone). The reaction may involve a sequential oxidative addition, two different types of three carbopalladations, and a Suzuki-type coupling.

    26. Hypergolic Ionic Liquids

      Hypergolic Ionic Liquids with the 2,2-Dialkyltriazanium Cation (pages 2792–2795)

      Haixiang Gao, Young-Hyuk Joo, Brendan Twamley, Zhiqiang Zhou and Jean'ne M. Shreeve

      Article first published online: 5 MAR 2009 | DOI: 10.1002/anie.200900094

      Thumbnail image of graphical abstract

      No flame, no gain: A hypergolic mixture is composed of stable species that readily react/ignite on molecular contact. Both the anion and the cation in an ionic liquid play prominent roles in determining hypergolic properties as well as ignition delay times. With the 2,2-dialkyltriazanium cation, salts with nitrate, chloride, nitrocyanamide, and dicyanamide anions are hypergolic.

    27. Iron Catalysis

      Iron-Mediated Cleavage of C[BOND]C Bonds in Vicinal Tricarbonyl Compounds in Water (pages 2796–2800)

      Jasmin Mecinović, Refaat B. Hamed and Christopher J. Schofield

      Article first published online: 11 MAR 2009 | DOI: 10.1002/anie.200806296

      Thumbnail image of graphical abstract

      Three of a kind: Vicinal tricarbonyl compounds undergo C[BOND]C cleavage mediated by ferric ions (see scheme). The observed cleavage of ninhydrin and dehydroascorbic acid has relevance for amino acid detection and the metabolism of vitamin C.

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    1. Preview: Angew. Chem. Int. Ed. 16/2009 (page 2805)

      Article first published online: 24 MAR 2009 | DOI: 10.1002/anie.200990077

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