Angewandte Chemie International Edition

Cover image for Angewandte Chemie International Edition

April 20, 2009

Volume 48, Issue 18

Pages 3193–3369

  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 Review
    9. Highlights
    10. Minireview
    11. Review
    12. Communications
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    1. Cover Picture: Direct C[BOND]H Metalation with Chromium(II) and Iron(II): Transition-Metal Host / Benzenediide Guest Magnetic Inverse-Crown Complexes (Angew. Chem. Int. Ed. 18/2009) (page 3193)

      Pablo Alborés, Luca M. Carrella, William Clegg, Pablo García-Álvarez, Alan R. Kennedy, Jan Klett, Robert E. Mulvey, Eva Rentschler and Luca Russo

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200990089

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      Chromation and ferration are the latest additions to the concept of alkali-metal-mediated metalation, as described by J. Klett, R. E. Mulvey, and co-workers in their Communication on page 3317 ff. While the more electropositive sodium is essential for the reaction, it is the less electropositive chromium or iron that actually performs deprotonation of benzene. This novel reactivity can be likened to a game of chess in which the queen (Na) holds the king in check, while the knight (Cr, Fe) scores checkm(etal)ate.

  2. Inside Cover

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    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
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    8. Book Review
    9. Highlights
    10. Minireview
    11. Review
    12. Communications
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    1. Inside Cover: Intermolecular Methoxycarbonylation of Terminal Alkynes Catalyzed by Palladium(II) Bis(oxazoline) Complexes (Angew. Chem. Int. Ed. 18/2009) (page 3194)

      Keisuke Kato, Satoshi Motodate, Tomoyuki Mochida, Takuya Kobayashi and Hiroyuki Akita

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200990090

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      Ein Bisoxazolin-Ligand erhöht die Präferenz von PdII für π-Systeme. Die direkte Umwandlung von terminalen Alkinen in β-Methoxyacrylate mit Komplexen solcher Bisoxazolin(box)-Liganden wird von K. Kato und Mitarbeitern in der Zuschrift auf S. 3326 ff. beschrieben. Dichtefunktionalrechnungen belegen, dass die π-Orbitale des Liganden in [Pd(box)(TFA)2] über die Doppelbindungen und die Peripherie delokalisiert sind und energetisch nahe dem LUMO liegen. Die Reaktion kann auch in einer Synthese von Kawain genutzt werden.

  3. Graphical Abstract

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    1. Graphical Abstract: Angew. Chem. Int. Ed. 18/2009 (pages 3197–3207)

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200990091

  4. Corrigendum

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    4. Graphical Abstract
    5. Corrigendum
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    9. Highlights
    10. Minireview
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    12. Communications
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    1. You have free access to this content
      A Belt-Shaped, Blue Luminescent, and Semiconducting Covalent Organic Framework (page 3207)

      Shun Wan, Jia Guo, Jangbae Kim, Hyotcherl Ihee and Donglin Jiang

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200990092

      This article corrects:

      A Belt-Shaped, Blue Luminescent, and Semiconducting Covalent Organic Framework

      Vol. 47, Issue 46, 8826–8830, Article first published online: 1 OCT 2008

  5. News

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  6. Author Profile

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    1. Stefan Mecking (page 3213)

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200900643

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      “My biggest motivation is to see my students′ progress. When I was eighteen I wanted to be unexcitingly, a chemist…!” This and more about Stefan Mecking can be found on page 3213.

  7. Book Review

    1. Top of page
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    1. Chirality in Transition Metal Chemistry.Molecules, Supramolecular Assemblies and Materials. By Hani Amouri and Michel Gruselle. (page 3214)

      Markus Albrecht

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200900912

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      John Wiley & Sons, Hoboken 2008. 260 pp., softcover € 47.90.—ISBN 978-0470060544

  8. Highlights

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    1. Endohedral Germanium Clusters

      The Shape of Germanium Clusters To Come (pages 3216–3217)

      Nikolaus Korber

      Article first published online: 12 MAR 2009 | DOI: 10.1002/anie.200900133

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      A different drummer: The existence of endohedral germanium clusters was predicted earlier by gas-phase experiments. The [Co@Ge10]3− anion now synthesized is surprising, as it breaks with a long line of exclusively deltahedral structures found in the past. Instead, it has a regular pentagonal-prismatic structure (see picture; Co gray, Ge red).

    2. Protein Design

      Allosteric Switches: Remote Controls for Proteins (pages 3218–3220)

      Thorsten Berg

      Article first published online: 11 MAR 2009 | DOI: 10.1002/anie.200806169

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      Long-distance service: Finding a selective small-molecule modulator for every domain of every human protein is a Herculean task. Wouldn't it be much easier to control the activity of any protein of choice by simply fusing it with a generally adaptable switch protein and controlling protein activity indirectly?

    3. Bryostatins

      Catalysis in the Total Synthesis of Bryostatin 16 (pages 3221–3223)

      Aubry K. Miller

      Article first published online: 3 MAR 2009 | DOI: 10.1002/anie.200900109

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      Adding up: A recent total synthesis of bryostatin 16 is highlighted by two transition-metal-catalyzed addition reactions. The first forges the B ring while establishing its relative stereochemistry. The second closes the macrocycle with a rare isomerization. These reactions neither require substrate activation nor do they generate byproducts. The powerful macrocyclization should be considered alongside more traditional methods.

  9. Minireview

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    1. Medicinal Chemistry

      Synthesis of Natural Product Inspired Compound Collections (pages 3224–3242)

      Kamal Kumar and Herbert Waldmann

      Article first published online: 6 MAR 2009 | DOI: 10.1002/anie.200803437

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      Mimicking nature synthetically: The successful development of multistep stereoselective syntheses gives access to natural product inspired compound collections having carbo-, oxa-,and azacyclic scaffold structures which promise to provide sources for new reagents in medicinal chemistry and chemical biology research.

  10. Review

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    1. Chromophores and π Systems

      Two-Photon Absorption and the Design of Two-Photon Dyes (pages 3244–3266)

      Miłosz Pawlicki, Hazel A. Collins, Robert G. Denning and Harry L. Anderson

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200805257

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      Two photons are better than one: This principle applies to a wide range of applications, ranging from engineering to physiology. Recent advances in our understanding of the phenomenon of two-photon absorption (see picture) and in the design of two-photon dyes are rapidly increasing the scope of this field.

  11. Communications

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    1. MicroRNA Detection

      Highly Sensitive Determination of microRNA Using Target-Primed and Branched Rolling-Circle Amplification (pages 3268–3272)

      Yongqiang Cheng, Xian Zhang, Zhengping Li, Xiaoxia Jiao, Yucong Wang and Yali Zhang

      Article first published online: 13 FEB 2009 | DOI: 10.1002/anie.200805665

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      One-nucleotide differences in microRNAs (miRNAs) can be discriminated in an assay based on a branched rolling-circle amplification (BRCA) reaction and fluorescence quantification. With the proposed method miRNA can be detected at concentrations as low as 10 fM, and the miRNA in a total RNA sample of a few nanograms can be determined.

    2. Organic Zeolites

      You have full text access to this OnlineOpen article
      Nitrogen and Hydrogen Adsorption by an Organic Microporous Crystal (pages 3273–3277)

      Kadhum J. Msayib, David Book, Peter M. Budd, Nhamo Chaukura, Kenneth D. M. Harris, Madeleine Helliwell, Steven Tedds, Allan Walton, John E. Warren, Mingcan Xu and Neil B. McKeown

      Article first published online: 2 APR 2009 | DOI: 10.1002/anie.200900234

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      Quick on the uptake: Following its identification during a targeted search, the intriguing crystal structure of 3,3′,4,4′-tetra(trimethylsilylethynyl)biphenyl was investigated. Simple removal of the included solvent provides an organic crystal with an open microporous structure that has a striking similarity to that of zeolite A (see picture). Reversible adsorption of nitrogen and hydrogen gases at 77 K confirms that the microporosity is permanent.

    3. Chiral Resolution

      Complete Chiral Resolution Using Additive-Induced Crystal Size Bifurcation During Grinding (pages 3278–3280)

      Wim L. Noorduin, Pim van der Asdonk, Hugo Meekes, Willem J. P. van Enckevort, Bernard Kaptein, Michel Leeman, Richard M. Kellogg and Elias Vlieg

      Article first published online: 25 MAR 2009 | DOI: 10.1002/anie.200806214

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      Grinding them down: By using a tailor-made additive, even in the absence of racemization in solution, abrasive grinding can yield an enantiopure solid state. This novel chiral resolution technique is based on an asymmetric bifurcation in the crystal size distribution as a result of stereoselective hampered crystal growth. R=o-tolyl.

    4. Biological Structures

      Click Chemistry for the Identification of G-Quadruplex Structures: Discovery of a DNA–RNA G-Quadruplex (pages 3281–3284)

      Yan Xu, Yuta Suzuki and Makoto Komiyama

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200806306

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      A trap that closes with a “click”: The copper-catalyzed azide–alkyne cycloaddition can occur in different G-quadruplex structures (see scheme). The species trapped by the click reaction can then be separated and analyzed. By using this approach, a DNA–RNA hybrid-type G-quadruplex structure formed by human telomeric DNA and RNA sequences was detected.

    5. Ion-Pair Receptors

      A Ditopic Ion-Pair Receptor Based on Stacked Nucleobase Quartets (pages 3285–3287)

      Tushar van der Wijst, Célia Fonseca Guerra, Marcel Swart, F. Matthias Bickelhaupt and Bernhard Lippert

      Article first published online: 31 MAR 2009 | DOI: 10.1002/anie.200900057

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      Pass the salt, please! State-of-the-art computations indicate that the stacking complex of a guanine quartet and an adenine quartet (G4A4) can function as a potent ditopic receptor for NaCl in aqueous solution (see picture; Na+, Cl yellow, O red, N blue, C black, H white).

    6. Heterocycles

      The Regio- and Stereoselective Synthesis of trans-2,3-Dihydropyridine N-oxides and Piperidines (pages 3288–3291)

      Hans Andersson, Magnus Gustafsson, Dan Boström, Roger Olsson and Fredrik Almqvist

      Article first published online: 25 MAR 2009 | DOI: 10.1002/anie.200900189

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      Reactivity N[BOND]Own: Pyridine N-oxides can be used for the complete regio- and stereoselective synthesis of trans-substituted piperidines. The sequential addition of Grignard reagents and aldehydes or ketones to pyridine N-oxides yields a complete regio- and stereoselective trans 2,3-addition reaction in high yields, and the substituted 2,3-dihydropyridine N-oxide can be reduced to form 2,3-trans-substituted piperidines (see scheme).

    7. PELDOR Spectroscopy

      Relative Orientation of Rigid Nitroxides by PELDOR: Beyond Distance Measurements in Nucleic Acids (pages 3292–3295)

      Olav Schiemann, Pavol Cekan, Dominik Margraf, Thomas F. Prisner and Snorri Th. Sigurdsson

      Article first published online: 25 MAR 2009 | DOI: 10.1002/anie.200805152

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      Show me your angle: Incorporation of the rigid spin label Ç allows determination of both distance and orientation of two nitroxide spin labels in DNA by PELDOR experiments at common X-band frequencies. The orientational information is obtained by varying the position of the detection pulses over the nitroxide spectrum. Simulation of the set of time traces yields very precise distances and angles.

    8. Heterocycles

      Copper-Catalyzed Direct C Arylation of Heterocycles with Aryl Bromides: Discovery of Fluorescent Core Frameworks (pages 3296–3300)

      Dongbing Zhao, Wenhai Wang, Fei Yang, Jingbo Lan, Li Yang, Ge Gao and Jingsong You

      Article first published online: 31 MAR 2009 | DOI: 10.1002/anie.200900413

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      A window of opportunity: A general copper-catalyzed C[BOND]H bond-activation path allows arylation of heterocycles with a wide range of aryl bromides (see scheme). The reaction shows excellent regioselectivity and exhibits good functional group tolerance. The 8-aryl xanthines exhibit fluorescence in a variety of solvents and show promise as reagents for biological imaging.

      Corrected by:

      Corrigendum: Copper-Catalyzed Direct C Arylation of Heterocycles with Aryl Bromides: Discovery of Fluorescent Core Frameworks

      Vol. 48, Issue 27, 4884, Article first published online: 17 JUN 2009

    9. Protein Design

      De Novo Design of a βαβ Motif (pages 3301–3303)

      Huanhuan Liang, Hao Chen, Keqiang Fan, Ping Wei, Xianrong Guo, Changwen Jin, Chen Zeng, Chao Tang and Luhua Lai

      Article first published online: 3 APR 2009 | DOI: 10.1002/anie.200805476

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      A designer monomeric protein with a βαβ fold—two parallel β strands connected by an α helix (see structure)—was constructed solely from coded amino acids. The high thermal stability of the structure is due to a large extent to tryptophan–tryptophan interactions between the two β strands.

    10. Nickel(III) Complexes

      Oxidation Reactivity of Bis(μ-oxo) Dinickel(III) Complexes: Arene Hydroxylation of the Supporting Ligand (pages 3304–3307)

      Kaoru Honda, Jaeheung Cho, Takahiro Matsumoto, Jungyun Roh, Hideki Furutachi, Takehiko Tosha, Minoru Kubo, Shuhei Fujinami, Takashi Ogura, Teizo Kitagawa and Masatatsu Suzuki

      Article first published online: 3 APR 2009 | DOI: 10.1002/anie.200900222

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      In the nick(el) of time: Bis(μ-oxo) dinickel(III) complexes 2 (see scheme), generated in the reaction of 1 with H2O2, are capable of hydroxylating the xylyl linker of the supporting ligand to give 3. Kinetic studies reveal that hydroxylation proceeds by electrophilic aromatic substitution. The lower reactivity than the corresponding μ-η22-peroxo dicopper(II) complexes can be attributed to unfavorable entropy effects.

    11. Colloids

      Schooling Behavior of Light-Powered Autonomous Micromotors in Water (pages 3308–3312)

      Michael Ibele, Thomas E. Mallouk and Ayusman Sen

      Article first published online: 31 MAR 2009 | DOI: 10.1002/anie.200804704

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      A new school of thought: Micrometer-sized silver chloride (AgCl) particles (red) in deionized water move under UV illumination by self-diffusiophoresis (see picture). Each AgCl particle secretes ions to which the other particles respond, and they are observed to “school” into regions with higher concentrations of particles. Photo-inactive silica particles (blue) also respond to the chemical secretion by swimming towards and surrounding individual AgCl particles.

    12. Si[BOND]Si Coupling

      Iron-Catalyzed Dehydrogenative Coupling of Tertiary Silanes (pages 3313–3316)

      Masumi Itazaki, Kensuke Ueda and Hiroshi Nakazawa

      Article first published online: 31 MAR 2009 | DOI: 10.1002/anie.200805112

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      A variety of tertiary silanes, even those with functional substituents, undergo an unprecedented iron-catalyzed dehydrogenative coupling (see scheme) in a convenient approach to disilanes, including unsymmetrical disilanes and polymers with Si[BOND]Si bonds in the backbone. Consideration of the catalytic reaction pathway revealed the intermediacy of a hydrido(disilyl)iron(IV) complex.

      Corrected by:

      Corrigendum: Iron-Catalyzed Dehydrogenative Coupling of Tertiary Silanes

      Vol. 48, Issue 38, 6938, Article first published online: 1 SEP 2009

    13. Inverse Crown Compounds

      You have full text access to this OnlineOpen article
      Direct C[BOND]H Metalation with Chromium(II) and Iron(II): Transition-Metal Host / Benzenediide Guest Magnetic Inverse-Crown Complexes (pages 3317–3321)

      Pablo Alborés, Luca M. Carrella, William Clegg, Pablo García-Álvarez, Alan R. Kennedy, Jan Klett, Robert E. Mulvey, Eva Rentschler and Luca Russo

      Article first published online: 20 JAN 2009 | DOI: 10.1002/anie.200805566

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      Check M(etal)ate: The chessboard and the figures represent a special reaction in which different low-polarity metals can metalate arenes directly when they are brought into the right position. In a combination of queen (sodium) and knight (chromium or iron), it is possible for the knight (usually the weaker piece) to make a direct deadly hit on the king (benzene) in this game of elemental chess.

    14. CO2 Reduction

      Conversion of Carbon Dioxide into Methanol with Silanes over N-Heterocyclic Carbene Catalysts (pages 3322–3325)

      Siti Nurhanna Riduan, Yugen Zhang and Jackie Y. Ying

      Article first published online: 31 MAR 2009 | DOI: 10.1002/anie.200806058

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      Activate and reduce: Carbon dioxide was reduced with silane using a stable N-heterocyclic carbene organocatalyst to provide methanol under very mild conditions. Dry air can serve as the feedstock, and the organocatalyst is much more efficient than transition-metal catalysts for this reaction. This approach offers a very promising protocol for chemical CO2 activation and fixation.

    15. Synthetic Methods

      Intermolecular Methoxycarbonylation of Terminal Alkynes Catalyzed by Palladium(II) Bis(oxazoline) Complexes (pages 3326–3328)

      Keisuke Kato, Satoshi Motodate, Tomoyuki Mochida, Takuya Kobayashi and Hiroyuki Akita

      Article first published online: 4 FEB 2009 | DOI: 10.1002/anie.200806080

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      Boxing clever: Direct conversion of a terminal alkyne group into a β-methoxyacrylate is realized with the aid of the bis(oxazoline) ligand (box). Acetyl and ketal protecting groups, free hydroxy groups, and acid-sensitive glycosidic bonds are not affected under the reaction conditions. The one-pot synthesis of (±)-dihydrokawain from the homopropargyl alcohol is also achieved. tfa=trifluoroacetate

    16. Micelles

      A New Two-Photon-Sensitive Block Copolymer Nanocarrier (pages 3329–3332)

      Jérôme Babin, Maxime Pelletier, Martin Lepage, Jean-François Allard, Denis Morris and Yue Zhao

      Article first published online: 2 APR 2009 | DOI: 10.1002/anie.200900255

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      Easily disrupted: Micelles of a new amphiphilic block copolymer that bear coumarin groups are sensitive to near infrared light by two-photon absorption of the chromophore. Disruption of the micelles under irradiation at 794 nm results in release of both photocleaved coumarin and encapsulated nile red from the hydrophobic core of micelle into aqueous solution, which results in opposing changes in fluorescence emission intensity.

    17. Synthetic Methods

      A Sequential O-Nitrosoaldol and Grignard Addition Process: An Enantio- and Diastereoselective Entry to Chiral 1,2-Diols (pages 3333–3336)

      Peng Jiao, Masanori Kawasaki and Hisashi Yamamoto

      Article first published online: 2 APR 2009 | DOI: 10.1002/anie.200900682

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      Chiral 1,2-diols have been prepared from α-aminoxylated aldehydes or cyclohexanone and Grignard reagents with L-proline or its tetrazole derivative as the catalyst. The presence of the ate complex of CeCl3⋅2 LiCl is essential for the high overall yields and good selectivities (see scheme; DMSO=dimethyl sulfoxide, THF=tetrahydrofuran, Tol=tolyl).

    18. Porphyrin Analogues

      Tetraazuliporphyrin Tetracation (pages 3337–3341)

      Natasza Sprutta, Stanisław Maćkowiak, Marzena Kocik, Ludmiła Szterenberg, Tadeusz Lis and Lechosław Latos-Grażyński

      Article first published online: 31 MAR 2009 | DOI: 10.1002/anie.200900496

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      At the crossroads: A unique carbon-bridged annulene motif—dehydroquatyrin—is imprinted into the molecular structure of the tetraazuliporphyrin tetracation (see picture). The macrocycle, which lies at the intersection of annulene, carbocation, and porphyrin chemistry, is obtained by the standard condensation of azulene and arylaldehyde followed by oxidation. The meso positions of the tetracation are susceptible to anionic or weak nucleophilic attack.

    19. Reactive Intermediates

      Structures and Properties of Nonchelated, d0 Alkyl Alkene Complexes of the Type [Cp2ZrMe(alkene)]+: Elusive Intermediates during Ziegler–Natta Polymerizations of Alkenes (pages 3342–3345)

      Francoise Sauriol, Elizabeth Wong, Angela M. H. Leung, Irja Elliott Donaghue, Michael C. Baird, Tebikie Wondimagegn and Tom Ziegler

      Article first published online: 2 APR 2009 | DOI: 10.1002/anie.200900379

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      Caught in the act: An alkyl alkene ZrIV complex (see picture; Cp=C5H5) has been synthesized and characterized for the first time. The alkene bonding mode is highly asymmetric, and C2 is quite carbocationic. There is also evidence for rotation about the C1[BOND]C2 bond. This extremely unusual complex provides an exemplar of previously unknown intermediates in Ziegler–Natta and carbocationic polymerization reactions of alkenes.

    20. Asymmetric Catalysis

      Enantioselective Friedel–Crafts Reactions in Water Using a DNA-Based Catalyst (pages 3346–3348)

      Arnold J. Boersma, Ben L. Feringa and Gerard Roelfes

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200900371

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      Taking the plunge: The first example of a Lewis acid catalyzed asymmetric Friedel–Crafts alkylation with olefins in water is described. By using loadings of a DNA-based copper catalyst as low as 0.15 mol %, good yields and excellent enantioselectivities were obtained in the reaction of α,β-unsaturated 2-acyl imidazoles with heteroaromatic π nucleophiles. dmbpy=4,4′-dimethyl-2,2′-bipyridine.

    21. Self-Assembled Structures

      A Supramolecular Hydrogen-Bonded Network as a Diffusion Barrier for Metal Adatoms (pages 3349–3352)

      Christophe Silien, Minna T. Räisänen and Manfred Buck

      Article first published online: 3 APR 2009 | DOI: 10.1002/anie.200806267

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      Confined in a molecular corral: A supramolecular network changes the mechanism by which underpotential deposition (UPD) of copper proceeds on a gold electrode modified by a self-assembled monolayer (SAM). Lateral diffusion of Cu adatoms is suppressed between adjacent cells of a network/SAM hybrid structure. Instead, UPD occurs by direct deposition into the SAM filled pores of the network, where the Cu adatoms are confined.

    22. Asymmetric Catalysis

      Direct anti-Selective Catalytic Asymmetric Mannich-Type Reactions of α-Ketoanilides for the Synthesis of γ-Amino Amides and Azetidine-2-amides (pages 3353–3356)

      Yingjie Xu, Gang Lu, Shigeki Matsunaga and Masakatsu Shibasaki

      Article first published online: 30 MAR 2009 | DOI: 10.1002/anie.200900670

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      Breaking with convention: A homodinuclear nickel complex derived from a biphenyldiamine-based Schiff base catalyzed an anti-selective Mannich-type reaction of α-ketoanilides (see scheme) to afford unique building blocks for the synthesis of azetidine-2-amides and α-hydroxy γ-amino amides. This approach stands in contrast to conventional Mannich-type reactions for the synthesis of β-amino carbonyl compounds. o-Ns=o-nitrobenzenesulfonyl.

    23. N2 Activation

      A Dinuclear Nickel(I) Dinitrogen Complex and its Reduction in Single-Electron Steps (pages 3357–3361)

      Stefan Pfirrmann, Christian Limberg, Christian Herwig, Reinhard Stößer and Burkhard Ziemer

      Article first published online: 25 MAR 2009 | DOI: 10.1002/anie.200805862

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      Electron by electron: β-Diketiminato nickel(I) complex fragments are capable of activating N2 through coordination. The resulting complex can be reduced in two single-electron steps, which further activates the N[BOND]N bond. The picture shows the structure of the singly reduced complex with μ-η11-bound N2.

    24. Enzyme Mechanism

      A Single Residue Influences the Reaction Mechanism of Ammonia Lyases and Mutases (pages 3362–3365)

      Sebastian Bartsch and Uwe T. Bornscheuer

      Article first published online: 2 APR 2009 | DOI: 10.1002/anie.200900337

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      All ways lead to Rome? Computer modeling and kinetic measurements identified a distinct residue in Phe/Tyr ammonia lyases (PAL/TAL) which controls whether the Friedel–Crafts or an E1cB reaction mechanism takes place. Hence, Glu484 in pcPAL favors the Friedel–Crafts reaction (see picture, MIO=4-methylidene imidazol-5-one) whereas an Asn in TAL gives an elimination reaction. These mechanistic investigations also reveal activity of a PAL mutant and a TAL towards an amino alcohol.

      Corrected by:

      Corrigendum: Corrigendum: A Single Residue Influences the Reaction Mechanism of Ammonia Lyases and Mutases

      Vol. 49, Issue 23, 3860, Article first published online: 17 MAY 2010

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    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. Corrigendum
    6. News
    7. Author Profile
    8. Book Review
    9. Highlights
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      Preview: Angew. Chem. Int. Ed. 19/2009 (page 3369)

      Article first published online: 15 APR 2009 | DOI: 10.1002/anie.200990094

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