Angewandte Chemie International Edition

Cover image for Angewandte Chemie International Edition

April 6, 2009

Volume 48, Issue 16

Pages 2807–2991

  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. Minireview
    10. Review
    11. Communications
    12. Preview
    1. Cover Picture: Direct Decomposition of Nitrous Oxide to Nitrogen by In Situ Oxygen Removal with a Perovskite Membrane (Angew. Chem. Int. Ed. 16/2009) (page 2807)

      Heqing Jiang, Haihui Wang, Fangyi Liang, Steffen Werth, Thomas Schiestel and Jürgen Caro

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200990078

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      Hollow fiber membranes from mixed-conducting perovskites can separate oxygen selectively from gas mixtures. Wall thicknesses as low as 150 μm can be obtained by a wet spinning process, and oxygen fluxes are thereby obtained that are relevant for technical applications. In their Communication on page 2983 ff., H. Wang, J. Caro and co-workers describe the complete decomposition of nitrous oxide with such membranes. This method offers new opportunities to reduce emissions of this greenhouse gas.

  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. Minireview
    10. Review
    11. Communications
    12. Preview
    1. Inside Cover: Perfluoropentaphenylborole (Angew. Chem. Int. Ed. 16/2009) (page 2808)

      Cheng Fan, Warren E. Piers and Masood Parvez

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200990079

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      Perfluoroaryl boranes are an important class of organometallic Lewis acids. The synthesis of perfluorinated compounds brings special challenges to tried-and-true synthetic methodologies. In their Communication on page 2955 ff., W. E. Piers and co-workers present the synthesis of a new, fully fluorinated heterocyclic borane that is also a member of the rare antiaromatic borole class of compounds. The route relies on normally facile transmetallation reactions made more difficult by the electron-withdrawing C6F5 groups of the target product.

  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. Minireview
    10. Review
    11. Communications
    12. 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. Minireview
    10. Review
    11. Communications
    12. 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. Minireview
    10. Review
    11. Communications
    12. Preview
    1. Olga V. Boltalina (page 2827)

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200990082

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      „I chose chemistry as a career because it gives me the opportunity to discover and make new things every day. When I wake up I use Skype to catch up with my son Stepan (who is currently finishing his PhD at MSU), since this time of day is the best compromise for our busy schedules given the 10 hour time-zone difference between Colorado and Moscow….“ This and more about Olga V. Boltalina can be found on page 2827.

  6. Book Review

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Author Profile
    7. Book Review
    8. Highlights
    9. Minireview
    10. Review
    11. Communications
    12. Preview
    1. Practical Microwave Synthesis for Organic Chemists.Strategies, Instruments, and Protocols. Edited by C. Oliver Kappe, Doris Dallinger and Shaun Murphree. (pages 2828–2829)

      Erik V.  Van der Eycken

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200900791

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      Wiley-VCH, Weinheim 2008. 300 pp., hardcover € 59.00.—ISBN 978-3527320974

  7. Highlights

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

      Beyond Reppe: Building Substituted Arenes by [2+2+2] Cycloadditions of Alkynes (pages 2830–2834)

      Brandon R. Galan and Tomislav Rovis

      Article first published online: 19 FEB 2009 | DOI: 10.1002/anie.200804651

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      Synthetic sequel: The transition-metal-catalyzed [2+2+2] cycloaddition is an established method for the construction of carbocyclic frameworks but is often plagued by poor selectivity. Recent literature paints a promising picture—a more general metal-catalyzed [2+2+2] cycloaddition can be accomplished intermolecularly using three separate alkynes to furnish highly substituted arenas (see scheme).

    2. Perfluorinated Boranes

      Perfluoropentaphenylborole: A New Approach to Lewis Acidic, Electron-Deficient Compounds (pages 2835–2837)

      Keith Huynh, Joan Vignolle and T. Don Tilley

      Article first published online: 19 MAR 2009 | DOI: 10.1002/anie.200900695

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      Zirconocene is the key: A new synthetic method, which utilizes zirconocene-mediated coupling of alkynes, has been developed for the preparation of a new class of highly Lewis acidic boroles (see scheme). Such compounds hold potential for applications in catalysis and the field of electron-deficient organic materials.

    3. Helical Structures

      Helical Arrangement of Porphyrins along DNA: Towards Photoactive DNA-Based Nanoarchitectures (pages 2838–2841)

      Hans-Achim Wagenknecht

      Article first published online: 3 MAR 2009 | DOI: 10.1002/anie.200900327

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      Stack them helically: A self-assembled helically stacked array of up to 11 porphyrin (Po)-modified uridines (red and blue in the double strand shown) is based on the supramolecular scaffold of duplex DNA and shows promising optical properties. Such architectures could find application as functional molecules for photoactive nanomaterials and photonic nanostructures.

  8. Minireview

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

      Molecular Catalysts that Oxidize Water to Dioxygen (pages 2842–2852)

      Xavier Sala, Isabel Romero, Montserrat Rodríguez, Lluís Escriche and Antoni Llobet

      Article first published online: 22 JAN 2009 | DOI: 10.1002/anie.200802659

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      Water into oxygen: A good catalyst for converting water into oxygen is seen as an essential part of any sustainable solar-energy conversion scheme. Some success has been achieved using molecular complexes as catalysts and the key factors influencing their performance are discussed. The necessity of generating a solid-state catalytic system is presented and the first attempts to generate supported molecular water-oxidation catalysts are analyzed.

  9. Review

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

      Redox Economy in Organic Synthesis (pages 2854–2867)

      Noah Z. Burns, Phil S. Baran and Reinhard W. Hoffmann

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200806086

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      Stimulus package for organic synthesis: The economy of step and atom usage has been widely reviewed and acknowledged as being useful frameworks to evaluate the efficiency of synthesis. This Review brings to attention another form of economy which should be considered in the planning and evaluation of a multistep synthesis: redox economy. Several guidelines and examples are included to illustrate the logic of this approach and to stimulate the design of syntheses.

  10. Communications

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

      Tandem Double-Michael-Addition/Cyclization/Acyl Migration of 1,4-Dien-3-ones and Ethyl Isocyanoacetate: Stereoselective Synthesis of Pyrrolizidines (pages 2868–2872)

      Jing Tan, Xianxiu Xu, Lingjuan Zhang, Yifei Li and Qun Liu

      Article first published online: 14 JAN 2009 | DOI: 10.1002/anie.200805703

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      Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU=1,8-diazabicyclo[5.4.0]undec-7-ene). Mechanisms for this atom-economic, one-pot synthesis have been proposed.

    2. Organic Crystals

      Rational Construction of 2D and 3D Borromean Arrayed Organic Crystals by Hydrogen-Bond-Directed Self-Assembly (pages 2873–2876)

      Yong-Biao Men, Junliang Sun, Zhi-Tang Huang and Qi-Yu Zheng

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200806198

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      Borromean organic networks: The rigid and trigonal pyramidal molecule, 1,3,5-tris(4-carboxyphenyl)adamantane (TCA), self-assembles into a 2D Borromean linked network by hydrogen bonds. Different linkers (methanol, phenazine, 4,4′-bipyridine, and 4,4′-azopyridine) result in more complex Borromean networks or a 3D polycatenation network.

    3. Bamboo-like Structures

      Undulated Multicompartment Cylinders by the Controlled and Directed Stacking of Polymer Micelles with a Compartmentalized Corona (pages 2877–2880)

      Bing Fang, Andreas Walther, Andrea Wolf, Youyong Xu, Jiayin Yuan and Axel H. E. Müller

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200806051

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      Like a bamboo rod: Long, bamboo-like undulated cylinders with distinct branch points and end groups (see picture) were obtained by the stacking of block terpolymer micelles that contain a fluorinated polybutadiene core and a compartmentalized corona of poly(4-tert-butoxystyrene) and poly(tert-butyl methacrylate). Stacking of the polymer micelles, which can be reversed, occurred when the solvent was changed from dioxane to ethanol.

    4. Metal–Semiconductor Nanostructures

      A General Approach to the Synthesis of Gold–Metal Sulfide Core–Shell and Heterostructures (pages 2881–2885)

      Zhenhua Sun, Zhi Yang, Jianhua Zhou, Man Hau Yeung, Weihai Ni, Hongkai Wu and Jianfang Wang

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200806082

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      Cores and effect: Water-dispersible core–shell structures and heterostructures incorporating gold nanocrystals of different shapes (polyhedra, cubes, and rods) and a variety of transition metal sulfide semiconductors (ZnS, CdS, NiS, Ag2S, and CuS) are synthesized using cetyltrimethylammonium bromide-encapsulated gold nanocrystals and metal thiobenzoates as starting materials.

    5. Enzyme Inhibition

      A Mechanism of Efficient G6PD Inhibition by a Molecular Clip (pages 2886–2890)

      Michael Kirsch, Peter Talbiersky, Jolanta Polkowska, Frank Bastkowski, Torsten Schaller, Herbert de Groot, Frank-Gerrit Klärner and Thomas Schrader

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200806175

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      Triple duty: A synthetic molecular clip traps nicotinamide adenine dinucleotide phosphate (NADP+; see picture) as well as occupying both the cofactor- and the substrate-binding site in glucose-6-phosphate (G6P) dehydrogenase. This combination of two inhibition mechanisms makes the clip highly effective and selective for this enzyme over other dehydrogenases.

    6. Surface Chemistry

      Pseudo-Bridging Silanols as Versatile Brønsted Acid Sites of Amorphous Aluminosilicate Surfaces (pages 2891–2893)

      Céline Chizallet and Pascal Raybaud

      Article first published online: 19 JAN 2009 | DOI: 10.1002/anie.200804580

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      Amorphization tunes acidity: Pseudo-bridging silanols, suggested as versatile Brønsted acid groups by molecular modeling studies, are obtained by shifted hydrolysis of Si[BOND]O[BOND]Al bridges formed by the thermal treatment of silica deposited on γ-Al2O3 (100), and appear under given pretreatment conditions. Demixing of part of the silica from the aluminosilicate phase is predicted upon excess water adsorption.

    7. Supramolecular Chemistry

      Supramolecular ABC Triblock Copolymers (pages 2894–2898)

      Ashootosh V. Ambade, Si Kyung Yang and Marcus Weck

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200805116

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      Just add it! Ruthenium initiators functionalized with hydrogen-bonding sites were utilized in ring-opening metathesis polymerization to prepare heterotelechelic polymers with hydrogen-bonding and metal-coordination units in a single step. Supramolecular ABC triblock copolymers were then self-assembled in one pot by simply adding complementary telechelic polymers to a solution of the heterotelechelic polymer (see picture).

    8. Hydrogen Storage

      Enhanced Hydrogen Storage by Palladium Nanoparticles Fabricated in a Redox-Active Metal–Organic Framework (pages 2899–2903)

      Young Eun Cheon and Myunghyun Paik Suh

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200805494

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      Quick on the uptake: Palladium nanoparticles were fabricated simply by immersing {[Zn3(ntb)2(EtOH)2]⋅4 EtOH}n (1) in an MeCN solution of Pd(NO3)2 at room temperature, without any extra reducing agent. 3 wt % PdNPs@[1]0.54+(NO3)0.54 significantly increase H2 uptake capacities, both at 77 K and 1 bar and at 298 K and high pressures (see picture, red curve) compared to [Zn3(ntb)2]n (black). ntb=4,4′,4′′-nitrilotrisbenzoate.

    9. EPR spectroscopy

      PELDOR Spectroscopy Distance Fingerprinting of the Octameric Outer-Membrane Protein Wza from Escherichia coli. (pages 2904–2906)

      Gregor Hagelueken, W. John Ingledew, Hexian Huang, Biljana Petrovic-Stojanovska, Chris Whitfield, Hassane ElMkami, Olav Schiemann and James H. Naismith

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200805758

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      Distance fingerprinting: Pulsed electron–electron double resonance spectroscopy (PELDOR) is applied to the octameric membrane protein complex Wza of E. coli. The data yielded a detailed distance fingerprint of its periplasmic region that compares favorably to the crystal structure. These results provide the foundation to study conformation changes from interaction with partner proteins.

    10. Hybrid Materials

      Incorporation of Fe3O4 Nanoparticles into Organometallic Coordination Polymers by Nanoparticle Surface Modification (pages 2907–2910)

      Sang Bok Kim, Chen Cai, Shouheng Sun and Dwight A. Sweigart

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200805773

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      Surface-modified Fe3O4nanoparticles (NPs) can be obtained by substituting [(η5-semiquinone)Mn(CO)3] for oleylamine surface protecting groups. The resulting NP can function as a nucleus or template to generate crystalline coordination polymers that contain superparamagnetic Fe3O4 NPs. Hybridized magnetic properties can be obtained by introducing paramagnetic metal nodes, such as Mn2+, into the polymers (see picture).

    11. Nonbonding Interactions

      Evidence for C[BOND]Cl/C[BOND]Br⋅⋅⋅π Interactions as an Important Contribution to Protein–Ligand Binding Affinity (pages 2911–2916)

      Hans Matter, Marc Nazaré, Stefan Güssregen, David W. Will, Herman Schreuder, Armin Bauer, Matthias Urmann, Kurt Ritter, Michael Wagner and Volkmar Wehner

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200806219

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      Attractive chlorine: Noncovalent interactions between chlorine or bromine atoms and aromatic rings in proteins open up a new method for the manipulation of molecular recognition. Substitution at distinct positions of two factor Xa inhibitors improves the free energy of binding by interaction with a tyrosine unit. The generality of this motif was underscored by multiple crystal structures as well as high-level quantum chemical calculations (see picture).

    12. Peptide Recognition

      Peptides Recognize Photoresponsive Targets (pages 2917–2920)

      Jing Chen, Takeshi Serizawa and Makoto Komiyama

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200900115

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      Clones on film: 7-mer peptides that bind to azobenzene-containing polymer films were selected from a phage library under visible light. Isolated clones showed greater affinities to the films under ultraviolet light than those under visible light. Furthermore, the peptide binding responds to the photoinduced isomerization of azobenzene groups.

    13. Supramolecular Polyvalency

      A Supramolecular Polymer as a Self-Assembling Polyvalent Scaffold (pages 2921–2924)

      Marion K. Müller and Luc Brunsveld

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200900143

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      Binding bacteria: Discotic molecules self-assemble into columnar supramolecular polymers that show strong polyvalent binding to bacteria by virtue of mannose ligands attached at their periphery (orange; see picture). The reversible formation of the supramolecular polymers allows simple mixing of differently substituted monomers and the optimization of bacterial aggregation.

    14. Cross-Coupling

      Iron-Catalyzed Chemoselective ortho Arylation of Aryl Imines by Directed C[BOND]H Bond Activation (pages 2925–2928)

      Naohiko Yoshikai, Arimasa Matsumoto, Jakob Norinder and Eiichi Nakamura

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200900454

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      No Fe-ar: Iron catalyzes an imine-directed C[BOND]H bond activation to introduce an ortho-aryl group to an acetophenone-derived imine using a diarylzinc reagent (see scheme), whereas palladium catalyzes the conventional substitution reaction . The title reaction features mild and selective C[BOND]H bond activation in the presence of aryl bromide, chloride, or sulfonate groups, and 1,2-dichloroisobutane is essential to achieve such selectivity.

    15. Synthetic Methods

      Direct Alkenylation of Indoles with α-Oxo Ketene Dithioacetals: Efficient Synthesis of Indole Alkaloids Meridianin Derivatives (pages 2929–2933)

      Haifeng Yu and Zhengkun Yu

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200900278

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      Let's make 'meri': Metal-free direct alkenylation of indoles was realized by acid-mediated substitution reactions of α-oxo ketene dithioacetals with indoles in trifluoroacetic acid/dichloromethane, selectively affording β-indolyl mono- and disubstituted α,β-unsaturated carbonyl compounds (see scheme). Condensation of the indolyl/ketene monothioacetals and guanidine nitrate efficiently produced meridianin derivatives.

    16. Gas-Phase Synthesis

      Gas-Phase Synthesis and Reactivity of the Lithium Acetate Enolate Anion, CH2CO2Li (pages 2934–2936)

      Matthew M. Meyer, George N. Khairallah, Steven R. Kass and Richard A. J. O'Hair

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200900245

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      Aerial pingpong: The lithium acetate enolate anion, the prototypical lithium salt of an α-deprotonated carboxylate, was prepared in the gas phase by electrospray ionization (ESI) and collision-induced ionization (CID). Its structure, reactivity, and energetics are presented along with the results of high-level computations.

    17. Synthetic Methods

      Nickel-Catalyzed Cross-Coupling of Non-activated and Functionalized Alkyl Halides with Alkyl Grignard Reagents (pages 2937–2940)

      Oleg Vechorkin and Xile Hu

      Article first published online: 28 JAN 2009 | DOI: 10.1002/anie.200806138

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      Reacting in the 'Ni'ck of time: The title reaction is realized by using an isolated NiII complex (1). The catalysis tolerates a wide range of important functional groups that are often incompatible with Grignard reagents in cross-coupling reactions.

    18. Natural Product Synthesis

      Total Synthesis of Ciguatoxin (pages 2941–2945)

      Akinari Hamajima and Minoru Isobe

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200805996

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      Something fishy: Ciguatoxin (see structure) is one of the principal toxins involved in ciguatera poisoning and the target of a total synthesis involving the coupling of three segments. The key transformations in this synthesis feature acetylene–dicobalthexacarbonyl complexation.

    19. Reaction Mechanisms

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      Mechanism of Cyclic Carbonate Synthesis from Epoxides and CO2 (pages 2946–2948)

      Michael North and Riccardo Pasquale

      Article first published online: 6 FEB 2009 | DOI: 10.1002/anie.200805451

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      Three interconnected catalytic cycles account for the title reaction catalyzed by a bimetallic aluminum(salen) complex and Bu4NBr. In the first, Bu4NBr acts as a nucleophile to activate the epoxide. In the second, Bu3N generated in situ serves to activate CO2. In the third, the aluminum(salen) complex brings the two activated species together so that the key bonds can be formed intramolecularly.

    20. Medicinal Chemistry

      Targeting Bone Metastases with a Bispecific Anticancer and Antiangiogenic Polymer–Alendronate–Taxane Conjugate (pages 2949–2954)

      Keren Miller, Rotem Erez, Ehud Segal, Doron Shabat and Ronit Satchi-Fainaro

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200805133

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      A polymer therapeutic designed for combination anticancer and antiangiogenic therapy inhibited the proliferation of prostate carcinoma cells and the proliferation, migration, and tube-formation of endothelial cells. The nanoconjugate was formed from an N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer, the bisphosphonate alendronate (for bone targeting), and the chemotherapy agent paclitaxel (PTX), which is cleaved by cathepsin B (see scheme).

    21. Fluoroaryl Boranes

      Perfluoropentaphenylborole (pages 2955–2958)

      Cheng Fan, Warren E. Piers and Masood Parvez

      Article first published online: 14 JAN 2009 | DOI: 10.1002/anie.200805865

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      Perfluorination: The fully fluorinated analogue of pentaphenylborole (see structure; B gray, C black, F green) has been prepared using successive transmetallation reactions involving Zr and Sn heterocycles. The highly moisture-sensitive borole is a new member of the perfluoroaryl borane family, a class of antiaromatic compounds of fundamental significance to concepts of aromaticity.

    22. Pericyclic Reactions

      A Preferred Disrotatory 4n Electron Möbius Aromatic Transition State for a Thermal Electrocyclic Reaction (pages 2959–2963)

      Michael Mauksch and Svetlana B. Tsogoeva

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200806009

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      Not forbidden: Thermal 4n electron electrocyclic reactions of Hückel topology structures proceed via “allowed” conrotatory pathways. However, for a Möbius topology, the Woodward–Hoffmann rules may be reversed and a “forbidden” disrotatory pathway can be preferred as shown theoretically for dodecahexaene 1 that transforms via a Heilbronner–Möbius aromatic transition structure 2 into a cyclic polyene 3.

    23. B[BOND]H Agostic Interactions

      Phosphinoborane and Sulfidoborohydride as Chelating Ligands in Polyhydride Ruthenium Complexes: Agostic σ-Borane versus Dihydroborate Coordination (pages 2964–2968)

      Yann Gloaguen, Gilles Alcaraz, Anne-Frédérique Pécharman, Eric Clot, Laure Vendier and Sylviane Sabo-Etienne

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200806178

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      A question of coordination mode: Two new borane compounds are prepared. They act as bifunctional ligands as illustrated by their reaction with ruthenium polyhydrides which leads to the formation of two complexes (see scheme) displaying either a δ-agostic interaction of a η2-B[BOND]H bond involving a trivalent boron atom or a dihydroborate ligation.

    24. Synthetic Methods

      Iron-Catalyzed Oxidative Heterocoupling Between Aliphatic and Aromatic Organozinc Reagents: A Novel Pathway for Functionalized Aryl–Alkyl Cross-Coupling Reactions (pages 2969–2972)

      Gérard Cahiez, Laura Foulgoc and Alban Moyeux

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200900175

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      Aryl–alkyl cross-coupling products are obtained by the iron-catalyzed oxidative heterocoupling of organozinc reagents under mild conditions. This novel reaction pathway is versatile, allowing for the use of primary and secondary aliphatic diorganozinc reagents as coupling partners as well as tolerating functionalized aryl- and alkylzinc reagents.

    25. A Dimeric Magnesium(I) Compound as a Facile Two-Center/Two-Electron Reductant (pages 2973–2977)

      Simon J. Bonyhady, Shaun P. Green, Cameron Jones, Sharanappa Nembenna and Andreas Stasch

      Article first published online: 17 MAR 2009 | DOI: 10.1002/anie.200900331

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      The odd couple: A dimeric magnesium(I) complex acts as a facile and selective two-center/two-electron reductant towards a series of unsaturated substrates (see scheme; Ar=2,6-iPr2C6H3, Ad=1-adamantyl). The novel reduced or reductively coupled products obtained from these reductions suggest that magnesium(I) compounds may find wide use in organic and organometallic syntheses.

    26. Picolyllithium

      Carbanion or Amide? First Charge Density Study of Parent 2-Picolyllithium (pages 2978–2982)

      Holger Ott, Ursula Pieper, Dirk Leusser, Ulrike Flierler, Julian Henn and Dietmar Stalke

      Article first published online: 13 MAR 2009 | DOI: 10.1002/anie.200806221

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      The negative charge originating from deprotonation of the methyl group is distributed over the 2-picolyl ring. Bonding properties derived from the electron density distribution support the enamide character of picolyllithium (PicLi; the picture shows the deformation density of [2-PicLi⋅PicH]2), but electrophilic attack occurs at the deprotonated C atom. This reactivity is rationalized by the electrostatic potential, which guides electrophiles towards the nucleophilic C atom.

    27. N2O Decomposition

      Direct Decomposition of Nitrous Oxide to Nitrogen by In Situ Oxygen Removal with a Perovskite Membrane (pages 2983–2986)

      Heqing Jiang, Haihui Wang, Fangyi Liang, Steffen Werth, Thomas Schiestel and Jürgen Caro

      Article first published online: 23 JAN 2009 | DOI: 10.1002/anie.200804582

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      Direct decomposition of N2O to N2 using perovskite hollow fiber membranes is achieved by combination with in situ oxygen removal (see picture). A coupled partial methane oxidation allows N2-free synthesis gas to be obtained. This sustainable process combines N2O removal with the simultaneous production of valuable chemicals.

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    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Author Profile
    7. Book Review
    8. Highlights
    9. Minireview
    10. Review
    11. Communications
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      Preview: Angew. Chem. Int. Ed. 17/2009 (page 2991)

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200990083

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