Chemistry - A European Journal

Cover image for Vol. 17 Issue 22

May 23, 2011

Volume 17, Issue 22

Pages 6013–6275

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Communications
    7. Full Papers
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    1. Cover Picture: F100388 (Chem. Eur. J. 22/2011) (page 6013)

      Oleg V. Maltsev, Dr. Alexander O. Chizhov and Prof. Dr. Sergei G. Zlotin

      Version of Record online: 16 MAY 2011 | DOI: 10.1002/chem.201190109

      Thumbnail image of graphical abstract

      Electrospray ionization mass spectrometry (ESI-MS) was used for the first time to study the deactivation pathways of Jørgensen–Hayashi-type catalysts modified with an ionic group in asymmetric Michael reactions. “Parasitic” oxidation and hydrolysis side reactions that poisoned the catalysts were identified. Other types of organocatalysts modified with ionic groups in various organocatalytic reactions may also be investigated by the approach described in the Full Paper by S. G. Zlotin et al. on page 6109 ff.

  2. Inside Cover

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    4. Graphical Abstract
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    1. Inside Cover: Hydrogen-Bonding Directed Assembly and Gelation of Donor–Acceptor Chromophores: Supramolecular Reorganization from a Charge-Transfer State to a Self-Sorted State (Chem. Eur. J. 22/2011) (page 6014)

      Anindita Das, Mijanur Rahaman Molla, Ambar Banerjee, Dr. Ankan Paul and Dr. Suhrit Ghosh

      Version of Record online: 16 MAY 2011 | DOI: 10.1002/chem.201190110

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      In a mixed assembly of bis-amide-functionalized dialkoxynaphthalene donor and naphthalenediimide acceptor, when there was a mismatch in the relative distance of the amide groups with respect to the two chromophores, self-sorting was observed. On the other hand if the two distances almost matched, a stable charge-transfer gel was formed in tetrachloroethylene. For more details see the Communication by S. Ghosh et al. on page 6061 ff.

  3. Graphical Abstract

    1. Top of page
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    3. Inside Cover
    4. Graphical Abstract
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  4. News

    1. Top of page
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    4. Graphical Abstract
    5. News
    6. Communications
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  5. Communications

    1. Top of page
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    4. Graphical Abstract
    5. News
    6. Communications
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    1. Asymmetric Catalysis

      Facile Creation of 2-Substituted Indolin-3-ones by Using Primary–Secondary Diamine Catalysts (pages 6030–6033)

      Wangsheng Sun, Liang Hong and Prof. Dr. Rui Wang

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201100144

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      2-Substitute an indole! The asymmetric organocatalytic conjugate addition of 1-acetylindolin-3-one to enones has been developed. This organocatalytic approach constitutes an easy and efficient method for the direct preparation of 2-substituted indolin-3-ones in high enantioselectivities (see scheme).

    2. Pnicogen Bonds

      Pnicogen Bonds: A New Molecular Linker? (pages 6034–6038)

      Stefan Zahn, René Frank, Prof. Eva Hey-Hawkins and Prof. Barbara Kirchner

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201002146

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      As strong as hydrogen bonds: An unexpected strong noncovalent interaction between atoms of the nitrogen group show a bond strength up to 28.0 kJ mol−1 and might act as a conceivable molecular linker (see graphic).

      Corrected by:

      Corrigendum: Corrigendum: Pnicogen Bonds: A New Molecular Linker?

      Vol. 19, Issue 5, 1526, Version of Record online: 17 JAN 2013

    3. Homogeneous Catalysis

      Palladium-Catalyzed Oxidative Trifluoromethylation of Indoles at Room Temperature (pages 6039–6042)

      Xin Mu, Shujun Chen, Dr. Xingliang Zhen and Prof. Dr. Guosheng Liu

      Version of Record online: 19 APR 2011 | DOI: 10.1002/chem.201100283

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      Trifluoromethylation of indoles has been performed successfully at room temperature by using a novel palladium-catalyzed oxidation strategy. In this reaction, PhI(OAc)2 has been used as an oxidant and TMSCF3 as a trifluoromethylation reagent (see scheme). A palladium(II/IV) mechanism has been proposed for the formation of the aryl C[BOND]CF3 bond.

    4. Hydrogen Storage

      Nanoconfinement and Catalytic Dehydrogenation of Ammonia Borane by Magnesium-Metal–Organic-Framework-74 (pages 6043–6047)

      Dr. Srinivas Gadipelli, Dr. Jamie Ford, Dr. Wei Zhou, Dr. Hui Wu, Dr. Terrence J. Udovic and Dr. Taner Yildirim

      Version of Record online: 20 APR 2011 | DOI: 10.1002/chem.201100090

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      Trapped and released: Ammonia borane (AB) incorporated within the one-dimensional hexagonal nanopores of magnesium-metal–organic-framework-74 shows clean and exceptionally improved H2-release properties when compared to pristine AB (see figure; C gray, O red, Mg green, H white, N blue, B orange). In this system, the kinetics and the temperature of AB dehydrogenation can be easily tuned.

    5. Organocatalysis

      Organocatalytic Enantioselective Formal Conjugate Addition of a Hydroxymoyl Anion to α,β-Unsaturated Aldehydes (pages 6048–6051)

      Beatriz Alonso, Dr. Efraím Reyes, Prof. Luisa Carrillo, Prof. Jose L. Vicario and Prof. Dr. Dolores Badía

      Version of Record online: 21 APR 2011 | DOI: 10.1002/chem.201100605

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      Umpoled oxime source: N-Nitromethylphthalimide is an excellent hydroxymetanimidoyl anion equivalent; under iminium catalysis and optimized reaction conditions, it undergoes a clean and highly enantioselective Michael addition to enals (see scheme). The nitro(phthalimido)methyl moiety can be then directly converted into an oxime moiety by a simple and high-yielding protocol.

    6. Cross-Coupling

      Nickel-Catalyzed Cross-Coupling of Aryl Bromides with Tertiary Grignard Reagents Utilizing Donor-Functionalized N-Heterocyclic Carbenes (NHCs) (pages 6052–6055)

      Claudia Lohre, Thomas Dröge, Dr. Congyang Wang and Prof. Dr. Frank Glorius

      Version of Record online: 20 APR 2011 | DOI: 10.1002/chem.201100909

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      One, two or three? The utilization of sterically hindered alkyl substrates represents a major challenge of the present cross-coupling methodology. The nickel-catalyzed Kumada cross- coupling of tertiary alkyl Grignard reagents with aryl bromides allows this difficult reaction with numerous different substrates. Optimal results were obtained using sterically demanding, bifunctional N-heterocyclic carbene ligands.

    7. Supported Catalysts

      A Highly Recyclable Magnetic Core-Shell Nanoparticle-Supported TEMPO catalyst for Efficient Metal- and Halogen-Free Aerobic Oxidation of Alcohols in Water (pages 6056–6060)

      Prof. Dr. Babak Karimi and Elham Farhangi

      Version of Record online: 19 APR 2011 | DOI: 10.1002/chem.201100047

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      Upping the tempo! A new, stable, TEMPO-based organocatalyst, supported on magnetic iron nanoparticles, provides a highly efficient heterogeneous catalyst 1 for the metal- and halogen-free aerobic oxidation of a wide range of primary, secondary, allylic, and even sterically hindered alcohols in water. After use, the catalyst was magnetically separated (see image) and reused for 20 consecutive rounds of reaction, without any significant loss in catalytic activity.

    8. Supramolecular Chemistry

      Hydrogen-Bonding Directed Assembly and Gelation of Donor–Acceptor Chromophores: Supramolecular Reorganization from a Charge-Transfer State to a Self-Sorted State (pages 6061–6066)

      Anindita Das, Mijanur Rahaman Molla, Ambar Banerjee, Dr. Ankan Paul and Dr. Suhrit Ghosh

      Version of Record online: 3 MAY 2011 | DOI: 10.1002/chem.201100606

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      Dynamic supramolecular assembly: Solvent polarity plays a critical role in hydrogen-bonding-mediated assembly of bis(amide)-functionalized naphthalenediimide acceptor and dialkoxynaphthalene donor chromophores. In tetrachloroethylene, a stable, charge-transfer (CT) gel was achieved, whereas in methylcyclohexane a CT state was initially formed that gradually switched over to the more stable self-sorted state (see graphic).

  6. Full Papers

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Communications
    7. Full Papers
    8. Preview
    1. Self-Assembly

      Pathway-Dependent Self-Assembly of Perylene Diimide/Peptide Conjugates in Aqueous Medium (pages 6068–6075)

      Yaron Tidhar, Dr. Haim Weissman, Dr. Sharon G. Wolf, Dr. Antonino Gulino and Dr. Boris Rybtchinski

      Version of Record online: 3 MAY 2011 | DOI: 10.1002/chem.201003419

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      Choose your path: Well-defined molecular systems exhibit kinetically controlled self-assembly in aqueous medium, enabling pathway-dependent assembly sequences, in which different organic nanostructures are evolved in a stepwise manner (see figure).

    2. Host–Guest Chemistry

      Electrostatic Barriers in Rotaxanes and Pseudorotaxanes (pages 6076–6087)

      Dr. Mohamad Hmadeh, Albert C. Fahrenbach, Dr. Subhadeep Basu, Dr. Ali Trabolsi, Dr. Diego Benítez, Hao Li, Dr. Anne-Marie Albrecht-Gary, Dr. Mourad Elhabiri and Prof. J. Fraser Stoddart

      Version of Record online: 15 APR 2011 | DOI: 10.1002/chem.201002933

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      Controlling molecular motions under water: Bipyridinium dications (BIPY2+) serve as effective electrostatic barriers towards slowing down the shuttling and threading motions of a cyclobis(paraquat-p-phenylene) tetracationic cyclophane in both rotaxane and pseudorotaxane systems in aqueous media. The presence of BIPY2+ units gives rise to self-folding and electrostatic repulsions that impose a considerable influence on the kinetic and thermodynamic processes occurring in these mechanically bonded and supramolecular systems.

    3. Donor–Acceptor Systems

      Regular Acyclic and Macrocyclic [AB] Oligomers by Formation of Push–Pull Chromophores in the Chain-Growth Step (pages 6088–6097)

      Dr. Fabio Silvestri, Dr. Markus Jordan, Dr. Kara Howes, Dr. Milan Kivala, Pablo Rivera-Fuentes, Prof. Dr. Corinne Boudon, Dr. Jean-Paul Gisselbrecht, Dr. W. Bernd Schweizer, Paul Seiler, Dr. Melanie Chiu and Prof. Dr. François Diederich

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201003672

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      This way and that way: Substrate scope and kinetic studies were conducted to identify appropriate monomers for oligomerization by [2+2] cycloaddition–cycloreversion, in which push–pull buta-1,3-dienes were formed in the chain-growth step (see scheme). Oligomerization yielded both macrocyclic and open-chain [AB] oligomers that were structurally characterized and exhibited intense intramolecular charge-transfer bands in their UV/Vis spectra.

    4. Self-Assembly

      Tubular or Subsurface Morphology of Octabutoxyphthalocyanine upon Self-Assembly in Polymer Matrices: Effect of the Casting Solvent (pages 6098–6108)

      Molla R. Islam and Prof. Pudupadi R. Sundararajan

      Version of Record online: 15 APR 2011 | DOI: 10.1002/chem.201003339

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      Caused by the solvent: The effect of the solvent on the morphology of self-assembled octabutoxyphthalocyanine in the presence of different polymer matrices was investigated by different spectroscopic and microscopic investigation methods, which revealed that tubular structures are formed from tetrachloroethane (TCE), whereas subsurface droplets are formed from chloroform (see figure).

    5. Organocatalysis

      Chiral Ionic Liquid/ESI-MS Methodology as an Efficient Tool for the Study of Transformations of Supported Organocatalysts: Deactivation Pathways of Jørgensen–Hayashi-Type Catalysts in Asymmetric Michael Reactions (pages 6109–6117)

      Oleg V. Maltsev, Dr. Alexander O. Chizhov and Prof. Dr. Sergei G. Zlotin

      Version of Record online: 6 MAY 2011 | DOI: 10.1002/chem.201100388

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      Poisonous parasites: Deactivation pathways of Jørgensen–Hayashi-type catalysts modified with an ionic group in asymmetric Michael reactions that involve an iminium-ion formation step have been studied by ESI-MS(+). “Parasitic” oxidation and hydrolysis side reactions that poisoned the catalysts were revealed (see image) along with a possible solution.

    6. Phosphatrozircenes

      Cycloheptatrienyl Zirconium Sandwich Complexes with Lewis Basic Phospholyl Ligands (Phosphatrozircenes): Synthesis, Structure, Bonding and Coordination Chemistry (pages 6118–6128)

      Dipl.-Chem. Andreas Glöckner, Dr. Thomas Bannenberg, Dr. Susanne Büschel, Dr. Constantin G. Daniliuc, Prof. Dr. Peter G. Jones and Prof. Dr. Matthias Tamm

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201100104

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      Molecular zwitters: Phospholylcycloheptatrienyl zirconium complexes exhibit ambiphilic reactivity and are able to develop unusual secondary interactions as a result of the isolobal replacement of a CH group in Lewis acidic [(η7-C7H7)Zr(η5-C5H5)] (trozircene) by a Lewis basic phosphorus atom; the bifunctional character of these molecules is illustrated by dimerisation in the solid state (see figure).

    7. Bond Theory

      A Continuous Symmetry Analysis of Chemical Bonding (pages 6129–6141)

      Dr. Chaim Dryzun, Dr. Pere Alemany, Dr. David Casanova and Prof. David Avnir

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201003093

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      The language of continuous symmetry measures (CSM) is used to explore the effects of symmetry breaking on chemical bonding by comparing the symmetry contents of the Hamiltonian, the electron density, the atomic populations, and the molecular orbitals for homonuclear A2 and heteronuclear AB diatomic molecules (see graph). This reveals quantitative relations between the covalency/ionicity of a chemical bond and the sources of asymmetry in the molecule.

    8. Asymmetric Synthesis

      Chiral Monofluorobenzyl Carbanions: Synthesis of Enantiopure β-Fluorinated β-Phenylethylamines (pages 6142–6147)

      Prof. Dr. José L. García Ruano, Dr. Alejandro Parra, Dr. Inés Alonso, Prof. Dr. Santos Fustero, Dr. Carlos del Pozo, Dr. Yolanda Arroyo and Dr. Ascensión Sanz-Tejedor

      Version of Record online: 13 APR 2011 | DOI: 10.1002/chem.201100455

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      A monofluorobenzyl carbanion can be stabilized by remote homochiral sulfinyl groups and reacts with N-sulfinylaldimines in a completely stereoselective manner (see scheme). Chiral auxiliaries can be removed with tBuLi without epimerization at the benzylic position. These reactions open a general route for preparing enantiomerically pure benzyl fluorides.

    9. Indium Complexes

      “Crowned” Univalent Indium Complexes as Donors? Experimental and Computational Insights on the Valence Isomers of EE′X4 Species (pages 6148–6161)

      Dr. Benjamin F. T. Cooper, Dr. Hiyam Hamaed, Warren W. Friedl, Michael R. Stinchcombe, Prof. Dr. Robert W. Schurko and Prof. Dr. Charles L. B. Macdonald

      Version of Record online: 15 APR 2011 | DOI: 10.1002/chem.201002946

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      Indium coronation: The donor chemistry of the univalent indium reagent [In([18]crown-6)][OTf] has been investigated by its reactions with InX3 (X=Cl, Br, I). The resultant donor–acceptor complexes of the form [X([18]crown-6)In[BOND]InX3] (X=Cl, Br, I) represent the first new isomeric form of indium(II) halides reported for several decades (see scheme; E=Al, Ga, In).

    10. Zeolite Crystallization

      UV–Raman and NMR Spectroscopic Studies on the Crystallization of Zeolite A and a New Synthetic Route (pages 6162–6169)

      Limin Ren, Dr. Caijin Li, Dr. Fengtao Fan, Qiang Guo, Desheng Liang, Prof. Zhaochi Feng, Prof. Can Li, Prof. Shougui Li and Prof. Feng-Shou Xiao

      Version of Record online: 13 APR 2011 | DOI: 10.1002/chem.201100098

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      Zeolite A crystals: The crystallization mechanism of zeolite A, determined by UV–Raman and NMR spectroscopic studies, shows that crystallization of zeolite A mainly occurs in the solid phase containing double four-ring units (see figure). Accordingly, a novel route for synthesizing zeolite A by mixing raw materials without additional water has been successfully designed.

    11. Reaction Mechanisms

      Stereochemistry and Mechanism of the Brønsted Acid Catalyzed Intramolecular Hydrofunctionalization of an Unactivated Cyclic Alkene (pages 6170–6178)

      Rachel E. McKinney Brooner and Prof. Ross A. Widenhoefer

      Version of Record online: 19 APR 2011 | DOI: 10.1002/chem.201003128

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      All in one step: Stereochemical and kinetic analysis of the Brønsted acid catalyzed intramolecular hydroamination/deuterioamination of an electronically unactivated cyclic alkene with a sulphonamide nucleophile was consistent with the concerted, anti addition of a proton/deuterium and nitrogen nucleophile across the C[DOUBLE BOND]C bond of the alkene (see scheme; DOTf= deuterated triflic acid, Ts=tosyl).

    12. Membrane Fusion Devices

      Design and Characterization of Endosomal-pH-Responsive Coiled Coils for Constructing an Artificial Membrane Fusion System (pages 6179–6186)

      Dr. Ayumi Kashiwada, Mana Tsuboi, Naohide Takamura, Enrico Brandenburg, Prof. Kiyomi Matsuda and Prof. Beate Koksch

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201003392

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      Haul up the target vesicles! A new example of a pH-responsive, target-selective membrane fusion device has been designed and synthesized in this study. The pilot liposomal vesicle bearing the device recognizes the target vesicle at physiological pH. A decline in pH to endosomal conditions “hauls up” the target vesicle and leads to fusion (see scheme).

    13. Nitrogen Heterocycles

      Ring-Closing Metathesis of Sulfoximine-Substituted N-Tethered Trienes: Modular Asymmetric Synthesis of Medium-Ring Nitrogen Heterocycles (pages 6187–6195)

      Dr. Vishal Mahajan and Prof. Dr. Hans-Joachim Gais

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201003172

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      Modular key: An asymmetric synthesis of highly substituted nine-, ten- and eleven-membered ring nitrogen heterocycles has been developed. Its key steps are 1) a modular synthesis of sulfoximine-substituted N-tethered trienes from the corresponding homoallylic amines and 2) a Ru-catalyzed ring-closing reaction of the sterically hindered trienes.

    14. Oxygen-Transfer Reactions

      Effect of the Axial Ligand on Substrate Sulfoxidation Mediated by Iron(IV)–Oxo Porphyrin Cation Radical Oxidants (pages 6196–6205)

      Dr. Devesh Kumar, Dr. G. Narahari Sastry and Dr. Sam P. de Visser

      Version of Record online: 5 APR 2011 | DOI: 10.1002/chem.201003187

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      All the substituent's trends: The sulfoxidation reactions of iron(IV)–oxo porphyrin cation radical complexes (see scheme) have been investigated by means of theoretical calculations. The correlations between the rate constant of substrate sulfoxidation and the ionization potential of the substrate as well as the hydrogen abstraction ability of the oxidant have been systematically identified.

    15. Heterogeneous Organocatalysis

      Heterogeneous Organocatalysis at Work: Functionalization of Hollow Periodic Mesoporous Organosilica Spheres with MacMillan Catalyst (pages 6206–6213)

      Jiao Yi Shi, Chang An Wang, Zhi Jun Li, Qiong Wang, Yuan Zhang and Prof. Dr. Wei Wang

      Version of Record online: 19 APR 2011 | DOI: 10.1002/chem.201100072

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      Mesoporous materials: Hollow-structured phenylene-bridged periodic mesoporous organosilica (PMO) spheres functionalized with the MacMillan catalyst (H-PhPMO-Mac) have been successfully prepared, which exhibit high activity and reusability in catalyzing asymmetric Diels–Alder reactions (see scheme).

    16. Cycloisomerization Reactions

      Gold- and Copper-Catalyzed Cycloisomerizations towards the Synthesis of Thujopsanone-Like Compounds (pages 6214–6220)

      Dr. Charles Fehr, Dr. Magali Vuagnoux, Dr. Andrea Buzas, Jeremy Arpagaus and Dr. Horst Sommer

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201002797

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      New reaction types have been discovered in the search for a new access to thujopsanone-related compounds by cycloisomerization reactions, and a variety of highly functionalized compounds has been accessed selectively by the proper choice of catalyst. For example, 2 underwent either cycloisomerization/[1,2]-acyl shift to give 1 or an unprecedented rearrangement/cycloaddition leading to a strained fused tricyclic ring system (3).

    17. Alkaloids

      Synthesis of (+)-Dumetorine and Congeners by Using Flow Chemistry Technologies (pages 6221–6226)

      Dr. Elena Riva, Dr. Anna Rencurosi, Dr. Stefania Gagliardi, Prof. Daniele Passarella and Dr. Marisa Martinelli

      Version of Record online: 19 APR 2011 | DOI: 10.1002/chem.201100300

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      Flow synthesis of natural products: The flow synthesis of (+)-dumetorine is described by the combination of five separate steps (see scheme). New protocols for performing classical reactions under continuous flow are disclosed as the RCM with novel PEG-supported Hoveyda catalyst and the unprecedented flow deprotection/Eschweiler–Clarke methylation sequence.

    18. DNA–Porphyrins

      Synthesis of β-Pyrrolic-Modified Porphyrins and Their Incorporation into DNA (pages 6227–6238)

      Dr. Adam W. I. Stephenson, Prof. Ashton C. Partridge and Dr. Vyacheslav V. Filichev

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201003200

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      i-Motif/triplex formation: Insertion of a β- pyrrolic-functionalised porphyrin into the middle of single-stranded CT oligonucleotides induces the formation of pH- and temperature-dependent i-motifs (see figure). Such aggregates can be dissociated by heat and due to their slow formation they do not interfere with duplex or triplex formation. Thermal stabilisation of parallel triplexes possessing a single porphyrin in TFO strands was observed, whereas anti-parallel duplexes were significantly destabilised.

    19. Organolanthanide Chemistry

      Substituent Size Effects in Lewis Base Induced Reductions in Organolanthanide Chemistry (pages 6239–6247)

      Daniel Bojer, Beate Neumann, Dr. Hans-Georg Stammler and Prof. Dr. Norbert W. Mitzel

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201002707

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      Divalent samarium complexes similar to 1 have been prepared through the reaction between triazacyclohexane derivatives and [Sm(AlMe4)3] and characterised by single-crystal X-ray diffraction and elemental analyses. A base-induced reduction and a C[BOND]H activation co-exist in the formation of these species; the relative abundances of these reaction channels can be tuned by varying the steric bulk of the substituent at the triazacyclohexane unit.

    20. C[BOND]H Activation

      C[BOND]H Activation versus Yttrium–Methyl Cation Formation from [Y(AlMe4)3] Induced by Cyclic Polynitrogen Bases: Solvent and Substituent-Size Effects (pages 6248–6255)

      Dr. Daniel Bojer, Dr. Ajay Venugopal, Dr. Andreas Mix, Beate Neumann, Dr. Hans-Georg Stammler and Prof. Dr. Norbert W. Mitzel

      Version of Record online: 18 APR 2011 | DOI: 10.1002/chem.201003317

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      Good things come in threes! The three nitrogen atoms in 1,3,5-triazacyclohexane ligands (L) act on [Y(AlMe4)3] in different ways, dependent on the nitrogen atom substituent. C[BOND]H activation is observed with isopropyl substituents to give [(L)Y(Me3AlCH2AlMe3)(μ-MeAlMe3)]; with cyclohexyl substituents dimethyl yttrium cations [(L)2YMe2][AlMe4] are formed (see figure).

    21. Oxidation Reactions

      Atmospheric-Pressure, Liquid-Phase, Selective Aerobic Oxidation of Alkanes Catalysed by Metal–Organic Frameworks (pages 6256–6262)

      Dr. Amarajothi Dhakshinamoorthy, Dr. Mercedes Alvaro and Prof. Dr. Hermenegildo Garcia

      Version of Record online: 14 APR 2011 | DOI: 10.1002/chem.201002664

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      Poring over alkanes: A catalyst based on a Fe(1,3,5-benzenetricarboxylate) metal–organic framework that incorporates N-hydroxyphthalimide as a radical initiator is used in the presence of molecular oxygen to effect alkane oxidation without the addition of solvent. This combination results in oxidised products in very good selectivity and reasonable conversion (see scheme).

    22. Magnetic Interactions

      High-Temperature Experimental and Theoretical Study of Magnetic Interactions in Diamond and Pseudo-Diamond Frameworks Built up from Hexanuclear Tantalum Clusters (pages 6263–6271)

      Dr. Berislav Perić, Dr. Stéphane Cordier, Jérôme Cuny, Dr. Régis Gautier, Thierry Guizouarn and Dr. Pavica Planinić

      Version of Record online: 15 APR 2011 | DOI: 10.1002/chem.201002332

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      Measuring magnetism: High-temperature susceptibility measurements and DFT calculations reveal the importance of inner ligands in magnetic interactions between cluster units in tantalum halide cluster compounds (see image). A magnetic model of the Heisenberg antiferromagnet accurately describes susceptibility at sufficiently high temperatures.

  7. Preview

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    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Communications
    7. Full Papers
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      Preview: Chem. Eur. J. 23/2011 (page 6275)

      Version of Record online: 16 MAY 2011 | DOI: 10.1002/chem.201190113

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