Chemistry - A European Journal

Cover image for Vol. 16 Issue 42

November 8, 2010

Volume 16, Issue 42

Pages 12493–12759

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
    1. Cover Picture: Nanocrystal-Based Time–Temperature Indicators (Chem. Eur. J. 42/2010) (page 12493)

      Dr. Jie Zeng, Stefan Roberts and Prof. Younan Xia

      Article first published online: 28 OCT 2010 | DOI: 10.1002/chem.201090207

      Thumbnail image of graphical abstract

      A new class of time–temperature indicatorsbased upon aqueous suspensions of triangular silver nanoplates with relatively sharp corners is reported in the Communication by Y. Xia and co-workers on page 12559 ff. When the nanoplates are subjected to aging in air at various temperatures or under different degrees of acceleration, the sharp corners will be gradually rounded, resulting in a progressive blueshift of the surface plasmon resonance peak accompanied by a series of distinctive colors.

  2. Inside Cover

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
    1. Inside Cover: Bulk and Surface Structure and High-Temperature Thermoelectric Properties of Inverse Clathrate-III in the Si-P-Te System (Chem. Eur. J. 42/2010) (page 12494)

      Dr. Julia V. Zaikina, Dr. Takao Mori, Dr. Kirill Kovnir, Dr. Detre Teschner, Dr. Anatoliy Senyshyn, Priv.-Doz. Dr. Ulrich Schwarz, Prof. Yuri Grin and Prof. Dr. Andrei V. Shevelkov

      Article first published online: 28 OCT 2010 | DOI: 10.1002/chem.201090208

      Thumbnail image of graphical abstract

      The fascinating crystal structure of type-III clathrates consisting of cage polyhedra of three types (shown in green, red, and blue in the picture) is not the only grace of the compounds in the Si-P-Te system. They combine effective charge-carrier transport and poor transport of heat with chemical stability in air up to 1500 K, making them a solid base for designing powerful thermoelectric materials for high-temperature power generation. For more details, see the Full Paper on page 12582 ff., by A. V. Shevelkov et al.

  3. Graphical Abstract

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
  4. News

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
  5. Minireview

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
    1. Natural Products

      Antibacterials from the Sea (pages 12512–12525)

      Dr. Chambers C. Hughes and Prof. William Fenical

      Article first published online: 15 SEP 2010 | DOI: 10.1002/chem.201001279

      Thumbnail image of graphical abstract

      Cures from the ocean: Marine organisms synthesize complex metabolites with antibacterial properties (see picture) to fend off co-occurring microbes. Representatives from each of five classes of natural products (ribosomal and non-ribosomal peptides, polyketides, alkaloids, and terpenes) isolated as new antibacterial metabolites from marine organisms are described (picture courtesy of X. Alvarez-Micó).

  6. Correspondence

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
    1. Nanorods

      Comment on: “Nucleation and Growth of BaFxCl2−x Nanorods” (pages 12526–12527)

      Prof. Frank Kubel and Dr. Hans-Rudolf Hagemann

      Article first published online: 12 OCT 2010 | DOI: 10.1002/chem.200900300

      Thumbnail image of graphical abstract

      From nanorods to microprisms: The crystal structure of recently reported Ba,F,Cl nanorods is shown to correspond to the structure of Ba7F12Cl2 (see picture), which can be prepared by several growth techniques.

    2. Reply to Comment on: “Nucleation and Growth of BaFxCl2−x Nanorods” (page 12528)

      Ming Gong, Ting Xie and Prof. Dr. Yadong Li

      Article first published online: 12 OCT 2010 | DOI: 10.1002/chem.201002516

      Thumbnail image of graphical abstract

      Taken in good faith: The structure of the nanorods indexed as “Ba2F3Cl” was based on the similiarity of the X-ray diffraction pattern with that given on the JCPDS card (No. 07-0029) for the above-mentioned structure. It appears, however, that the structure should have been indexed as “Ba7F12Cl2” in line with more recent results.

  7. Communications

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
    1. Alumoxanes

      Trinuclear Alumoxanes with an Acyclic Al-O-Al-O-Al Core and Studies of Their Reactivity (pages 12530–12533)

      Dr. Ying Yang, Prof. Dr. Hongping Zhu, Prof. Dr. Herbert W. Roesky, Dr. Zhi Yang, Gengwen Tan, Dr. Haipu Li, Dr. Michael John and Dr. Regine Herbst-Irmer

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201002118

      Thumbnail image of graphical abstract

      No cycle this time: The first trinuclear alumoxanes [{LAlR(μ-O)}2AlMe] (L=CH[C(Me)N(Ar)]2; Ar=2,6-iPr2C6H3; R=Me, Et, Ph) with an acyclic Al-O-Al-O-Al core were synthesized (see scheme). The ethyl and phenyl derivatives were characterized by X-ray spectroscopy. When treated with AlMe3, [{LAlR(μ-O)}2AlMe] (R=Me, Ph) gave tetranuclear alumoxanes bearing a (Me2AlO)2 four-membered ring.

    2. Asymmetric Synthesis

      Bicyclic Guanidine-Catalyzed Direct Asymmetric Allylic Addition of N-Aryl Alkylidene-Succinimides (pages 12534–12537)

      Jianmin Wang, Hongjun Liu, Yitian Fan, Yuanyong Yang, Prof. Dr. Zhiyong Jiang and Prof. Dr. Choon-Hong Tan

      Article first published online: 23 SEP 2010 | DOI: 10.1002/chem.201002183

      Thumbnail image of graphical abstract

      Enantio-enriched maleimides and succinimides that can be used to prepare aza-heterocycles with multiple chiral centers are obtained from the bicyclic guanidine-catalyzed direct asymmetric allylic addition of N-aryl alkylidene-succinimides to imines. NMR studies and deuterium-exchange experiments were used to study the intermediates in the reaction.

    3. C[BOND]C Activation

      Carbon–Carbon Bond Cleavage by Strongly Electrophilic Boranes (pages 12538–12540)

      Dr. Bao-Hua Xu, Dr. Gerald Kehr, Dr. Roland Fröhlich and Prof. Dr. Gerhard Erker

      Article first published online: 28 SEP 2010 | DOI: 10.1002/chem.201002047

      Thumbnail image of graphical abstract

      Make and break: Strongly electrophilic boranes RB(C6F5)2 (R=Me, CH2CH2Ph) react with an aminodihydropentalene substrate by C[DOUBLE BOND]C bond cleavage with concomitant borylene insertion to yield the ring-enlarged zwitterionic borate/iminium product.

    4. Organocatalysis

      An Organocatalytic [3+2] Cyclisation Strategy for the Highly Enantioselective Synthesis of Spirooxindoles (pages 12541–12544)

      Dr. Arnaud Voituriez, Nathalie Pinto, Mathilde Neel, Pascal Retailleau and Dr. Angela Marinetti

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201001791

      Thumbnail image of graphical abstract

      Power of P: Phosphine-promoted [3+2] annulation reactions between electron-poor allenes and 3-arylidene indolin-2-ones afford a new organocatalytic strategy for the synthesis of the spirocyclic core of oxindolic cyclopentanes (see scheme). Asymmetric variants of these reactions have been implemented by using chiral catalysts, giving very high levels of asymmetric induction.

    5. Dendron–Polyoxometalate Hybrids

      Manipulation of Ordered Nanostructures of Protonated Polyoxometalate through Covalently Bonded Modification (pages 12545–12548)

      Yongliang Wang, Xiaole Wang, Dr. Xinjun Zhang, Nan Xia, Bo Liu, Jie Yang, Wei Yu, Minbiao Hu, Dr. Miao Yang and Prof. Wei Wang

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201001674

      Thumbnail image of graphical abstract

      Let there be order: By covalently grafting first- and second-generation dendrons to a polyoxometalate (POM), lamellar or cylindrical nanostructures of the protonated dendron-POM-dendron hybrids have been constructed (see figure), which may open an avenue to the future fabrication of novel solid proton conductors with highly ordered structures.

    6. Silicon Organocatalysis

      Silylated Pyrrolidines as Catalysts for Asymmetric Michael Additions of Aldehydes to Nitroolefins (pages 12549–12552)

      Ralph Husmann, Manuel Jörres, Prof. Dr. Gerhard Raabe and Prof. Dr. Carsten Bolm

      Article first published online: 28 SEP 2010 | DOI: 10.1002/chem.201001764

      Thumbnail image of graphical abstract

      Silicon can! A convenient synthesis of enantiopure (S)-2-(diphenylmethylsilyl)pyrrolidine is described and its organocatalytic activity in asymmetric Michael reactions is demonstrated (see scheme). By using 10 mol % of this novel organocatalyst, the addition of aldehydes to nitroolefins affords products with high stereoselectivities (d.r. ≤97:3 and e.r. ≤95:5) in yields up to 99 %.

    7. Silyl-Modified Analogues of 2-Tritylpyrrolidine: Synthesis and Applications in Asymmetric Organocatalysis (pages 12553–12558)

      Dipl.-Chem. Jonathan O. Bauer, Dipl.-Chem. Julian Stiller, Dr. Eugenia Marqués-López, Dr. Katja Strohfeldt, Prof. Dr. Mathias Christmann and Prof. Dr. Carsten Strohmann

      Article first published online: 28 SEP 2010 | DOI: 10.1002/chem.201002166

      Thumbnail image of graphical abstract

      Silicon-based organocatalysts: In an effort to study the effects of substituting carbon by silicon within the catalyst backbone, we developed an efficient synthesis of (S)-2-triphenylsilylpyrrolidine [(S)-2]. The evaluation of (S)-2 against its carbon analogue (S)-1 in two organocatalytic reactions is complemented by computational studies.

    8. Sensors

      Nanocrystal-Based Time–Temperature Indicators (pages 12559–12563)

      Dr. Jie Zeng, Stefan Roberts and Prof. Younan Xia

      Article first published online: 13 OCT 2010 | DOI: 10.1002/chem.201002665

      Thumbnail image of graphical abstract

      Sharp change indicators: A new class of time–temperature indicators (TTIs) based upon aqueous suspensions of triangular silver nanoplates with relatively sharp corners has been developed. Such nanoplates display localized surface plasmon resonance peaks in the visible region, the positions of which are highly sensitive to the sharpness of the corners.

    9. Nitrogen Fixation

      N2 Activation by a Hafnium Complex: A DFT Study on CO-Assisted Dinitrogen Cleavage and Functionalization (pages 12564–12569)

      Xinhao Zhang, Burkhard Butschke and Helmut Schwarz

      Article first published online: 28 SEP 2010 | DOI: 10.1002/chem.201001635

      Thumbnail image of graphical abstract

      Let's break it completely: Activation and functionalization of dinitrogen constitute challenging goals. Chirik and co-workers have studied the reaction of a hafnocene–dinitrogen complex with CO in the course of which the N[BOND]N bond is completely broken. Computational studies on mechanistic features of this particular reaction show that migratory insertion of CO into the Hf[BOND]N bond, that is, C[BOND]N bond formation, is easy and that the release of ring strain of a four-membered Hf-C-N-N ring provides the driving force for N[BOND]N bond scission.

  8. Full Papers

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

      The Dynamic Chemistry of Molecular Borromean Rings and Solomon Knots (pages 12570–12581)

      Dr. Cari D. Meyer, Dr. Ross S. Forgan, Dr. Kelly S. Chichak, Dr. Andrea J. Peters, Nicholas Tangchaivang, Dr. Gareth W. V. Cave, Dr. Saeed I. Khan, Dr. Stuart J. Cantrill and Prof. J. Fraser Stoddart

      Article first published online: 22 OCT 2010 | DOI: 10.1002/chem.201001806

      Thumbnail image of graphical abstract

      One thing one minute and another the next: The dynamic solution equilibria between molecular Borromean rings and Solomon knots (see figure) are examined with respect to synthetic conditions, choice of metal template, and crystallization protocols in the self-assembly of these topologically complex mechanically interlocked architectures.

    2. Clathrates

      Bulk and Surface Structure and High-Temperature Thermoelectric Properties of Inverse Clathrate-III in the Si-P-Te System (pages 12582–12589)

      Dr. Julia V. Zaikina, Dr. Takao Mori, Dr. Kirill Kovnir, Dr. Detre Teschner, Dr. Anatoliy Senyshyn, Priv.-Doz. Dr. Ulrich Schwarz, Prof. Yuri Grin and Prof. Dr. Andrei V. Shevelkov

      Article first published online: 13 OCT 2010 | DOI: 10.1002/chem.201001990

      Thumbnail image of graphical abstract

      Thermoelectric Si-P-Te clathrate-III: Si-P-Te clathrate-III has been developed as a new high-temperature thermoelectric material. Its utmost stability (up to 1500 K) in air is the result of the formation of a nanosized surface layer of phosphorus-doped silica. The as-prepared Si-P-Te clathrate displays high values of the thermoelectric figure-of-merit at temperatures up to 1100 K (see figure). Further methods of thermoelectric efficiency optimization for Si-P-Te clathrates are discussed.

    3. Cavitands

      FRET Studies on a Series of BODIPY-Dye-Labeled Switchable Resorcin[4]arene Cavitands (pages 12590–12602)

      Igor Pochorovski, Benjamin Breiten, Dr. W. Bernd Schweizer and Prof. Dr. François Diederich

      Article first published online: 23 SEP 2010 | DOI: 10.1002/chem.201001625

      Thumbnail image of graphical abstract

      Shed light on it! A series of BODIPY-dye-labeled resorcin[4]arene cavitands with oligo(phenylene–ethynylene) spacers of different lengths were synthesized; their pH- and temperature-dependent switching behavior was studied. Distance parameters from X-ray structures of synthetic intermediates combined with results from fluorescence resonance energy transfer (FRET) studies enabled the determination of the average opening angle (α) of the cavitands in the vase conformation in solution (see scheme).

    4. Cluster Compounds

      Molecular Gallium Arsenide Phosphide Clusters Prepared from AsP3, P4, and [{GaC(SiMe3)3}4] (pages 12603–12608)

      Brandi M. Cossairt and Prof. Christopher C. Cummins

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201001819

      Thumbnail image of graphical abstract

      When tetrahedra collide: The reaction of AsP3 with [{GaC(SiMe3)3}4] provides access to molecular gallium arsenide phosphide clusters. In particular, [As{GaC(SiMe3)3}3P3] was prepared, in which three {GaC(SiMe3)3} units have inserted into all three AsP bonds of AsP3, with a lone Ga-supported As atom and an intact cyclo-P3 ring (see graphic).

    5. Host–Guest Systems

      Excited-State Prototropic Equilibrium Dynamics of 6-Hydroxyquinoline Encapsulated in Microporous Catalytic Faujasite Zeolites (pages 12609–12615)

      Sun-Young Park, Hyunung Yu, Jiho Park and Du-Jeon Jang

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201000734

      Thumbnail image of graphical abstract

      Equilibrium dynamics in zeolites: Excited-state proton transfer and geminate recombination of 6-hydroxyquinoline encaged in faujasite zeolites (see picture) have been investigated. Proton transfer at each tautomerization step of 6-hydroxyquinoline is in competition with geminate recombination due to the confined environment of dehydrated zeolitic supercages. Thus, excited-state equilibria among three prototropic species of 6-hydroxyquinoline are established.

    6. Asymmetric Synthesis

      High-Yielding Synthesis of the Anti-Influenza Neuraminidase Inhibitor (−)-Oseltamivir by Two “One-Pot” Sequences (pages 12616–12626)

      Dr. Hayato Ishikawa, Takaki Suzuki, Dr. Hideo Orita, Dr. Tadafumi Uchimaru and Prof. Dr. Yujiro Hayashi

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201001108

      Thumbnail image of graphical abstract

      Fighting the flu: Two “one-pot” and column-free asymmetric sequences are used to accomplish the synthesis of (−)-oseltamivir, known as the anti-influenza drug Tamiflu (see scheme; TMS: trimethylsilyl). This high-yielding synthesis takes advantage of a diphenylprolinol silyl ether as an organocatalyst and single-pot domino operations.

      Corrected by:

      Corrigendum: Corrigendum: High-Yielding Synthesis of the Anti-Influenza Neuraminidase Inhibitor (−)-Oseltamivir by Two “One-Pot” Sequences

      Vol. 17, Issue 44, 12227, Article first published online: 17 OCT 2011

    7. Oligosaccharides

      Synthesis of the Core Structure of the Lipoteichoic Acid of Streptococcus pneumoniae (pages 12627–12641)

      Dr. Christian Marcus Pedersen, Dr. Ignacio Figueroa-Perez, Dr. Joshodeep Boruwa, Dr. Buko Lindner, Prof. Dr. Artur J. Ulmer, Prof. Dr. Ulrich Zähringer and Prof. Dr. Richard R. Schmidt

      Article first published online: 28 SEP 2010 | DOI: 10.1002/chem.201001204

      Thumbnail image of graphical abstract

      The core: The synthesized core structure (1) of S. pneumoniae LTA (lipoteichoic acid) exhibited similar stimulation of interleukin-8 release as the recently synthesized complete LTA consisting of the core structure and the pseudopentasaccharidic repeating unit. Contrary to previous postulations, TLR2 is not the signalling receptor for these compounds.

    8. Photochromism

      Syntheses and Photophysical Properties of N-Pyridylimidazol-2-ylidene Tetracyanoruthenates(II) and Photochromic Studies of Their Dithienylethene-Containing Derivatives (pages 12642–12649)

      Dr. Gongping Duan and Prof. Dr. Vivian Wing-Wah Yam

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201000880

      Thumbnail image of graphical abstract

      Enlightening chemistry: Luminescent tetracyanoruthenates(II) with chelating pyridyl N-heterocyclic carbene ligands have been synthesized and their dithienylethene-containing complexes have been shown to display interesting photochromic properties (see figure).

    9. Unnatural Base Pairs

      Solution Structure, Mechanism of Replication, and Optimization of an Unnatural Base Pair (pages 12650–12659)

      Denis A. Malyshev, Danielle A. Pfaff, Shannon I. Ippoliti, Dr. Gil Tae Hwang, Prof. Tammy J. Dwyer and Prof. Floyd E. Romesberg

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201000959

      Thumbnail image of graphical abstract

      Optimization of the unnatural: A variety of derivatized unnatural base pairs have been synthesized and their structures and DNA polymerase-mediated replication have been evaluated (see graphic). The data elucidate the mechanism of replication and one pair, dDMO–d5SICS, represents significant progress towards the expansion of the genetic alphabet.

    10. Natural Products

      The Total Synthesis of (±)-Fumimycin (pages 12660–12667)

      Dipl.-Chem. Patrick J. Gross and Prof. Dr. Stefan Bräse

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201001036

      Thumbnail image of graphical abstract

      Peptide deformylase (PDF)-inhibitor synthesis: A strategy involving amine formation through addition to a ketimine has been successfully employed for the first total synthesis of the antibiotic agent fumimycin (see scheme).

    11. Cyclization

      Cyclization of Zincated α-N-Homoallylamino Nitriles: A New Entry to Enantiopure 2,3-Methanopyrrolidines (pages 12668–12677)

      Sabrina Ouizem, Dr. Sandrine Cheramy, Dr. Candice Botuha, Prof. Fabrice Chemla, Dr. Franck Ferreira and Dr. Alejandro Pérez-Luna

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201001639

      Thumbnail image of graphical abstract

      Cycling with zinc: Zincated α-N-homoallylamino nitriles lead to 2,3-methanopyrrolidines in good yields and excellent selectivities (see scheme; LDA= lithium diisopropylamide). The cyclization occurs with a stereospecific inversion of the homoallylic stereogenic center, which has been rationalized by a mechanism involving the formation of a zincioiminium ion that undergoes an aza-Cope rearrangement followed by [3+2] cycloaddition.

    12. Carbamates

      Atropisomerism of Aromatic Carbamates (pages 12678–12682)

      Prof. Dr. Lutz F. Tietze, Dr. Heiko J. Schuster, Dr. J. Marian von Hof, Dipl.-Chem. Sonja M. Hampel, Dr. Juan F. Colunga and Dr. Michael John

      Article first published online: 30 SEP 2010 | DOI: 10.1002/chem.201001047

      Thumbnail image of graphical abstract

      In a tight spot: The depicted N-aryl-N-alkylcarbamate (Bn=benzyl) exists as four atropo-diastereomers at room temperature due to hindered rotation about the N[BOND]aryl and N[BOND]C(O) bonds. By using 2D exchange NMR spectroscopy (EXSY), the height of the rotational barriers could be determined and compared to those of three related compounds.

    13. TNT Detection

      Ultrasensitive SERS Detection of TNT by Imprinting Molecular Recognition Using a New Type of Stable Substrate (pages 12683–12693)

      Liangbao Yang, Liang Ma, Guangyu Chen, Jinhuai Liu and Prof. Zhong-Qun Tian

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201001053

      Thumbnail image of graphical abstract

      SERS substrates: The ultra-trace detection of TNT based on surface-enhanced Raman scattering (SERS) is reported. The method relies on π-donor–acceptor interactions between the π-acceptor TNT and the π-donor p,p′-dimercaptoazobenzene (DMAB), with the latter serving to cross-link silver nanoparticles deposited on the surface of silver molybdate nanowires (see scheme).

    14. Carbon Dioxide Storage

      High CO2 Storage Capacity in Alkali-Promoted Hydrotalcite-Based Material: In Situ Detection of Reversible Formation of Magnesium Carbonate (pages 12694–12700)

      Dr. Stéphane Walspurger, Paul D. Cobden, Dr. Olga V. Safonova, Dr. Yinghai Wu and Dr. Edward J. Anthony

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201000687

      Thumbnail image of graphical abstract

      CO2sponge cleans up! K2CO3-promoted hydrotalcite shows outstanding CO2 storage capacity at relatively high temperature and pressure. In situ structural studies demonstrate that magnesium oxide centres of the hydrotalcite-based materials are converted to magnesium carbonate above 300 °C under sufficient CO2 and steam pressure (see picture).

    15. Crystal Structures

      Crystal Structure Prediction and Isostructurality of Three Small Molecules (pages 12701–12709)

      Dr. Aldi Asmadi, Dr. John Kendrick and Dr. Frank J. J. Leusen

      Article first published online: 20 SEP 2010 | DOI: 10.1002/chem.200903227

      Thumbnail image of graphical abstract

      Discovering the unknown: This computational study explores the relationship between the molecular structure and the solid-state structure for three small molecules (see scheme) that are known to crystallise in distinct crystal structures. By using accurate lattice-energy calculation tools, it is predicted that another, as yet undiscovered, polymorph should exist for the dimethyl-substituted compound.

    16. Conjugated Polymers

      Control of the Optical Properties of a Star Copolymer with a Hyperbranched Conjugated Polymer Core and Poly(ethylene glycol) Arms by Self-Assembly (pages 12710–12717)

      Feng Qiu, Chunlai Tu, Yan Chen, Yunfeng Shi, Liang Song, Ruibing Wang, Prof. Xinyuan Zhu, Prof. Bangshang Zhu, Prof. Deyue Yan and Prof. Tao Han

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201001084

      Thumbnail image of graphical abstract

      Tuning a star copolymer: A star copolymer (HCP-star-PEG) with a hyperbranched conjugated (HCP) core and many poly(ethylene glycol) (PEG) arms has been synthesized through an acylhydrazone connection. The optical properties of HCP-star-PEG changed on complexation of acid (see figure). With different proportions of chloroform and acetonitrile, the optical properties of HCP-star-PEG can be easily controlled by self-assembly of the star polymer.

    17. Heterogeneous Catalysis

      Simple Preparation and Application of TEMPO-Coated Fe3O4 Superparamagnetic Nanoparticles for Selective Oxidation of Alcohols (pages 12718–12726)

      Alexander K. Tucker-Schwartz and Prof. Dr. Robin L. Garrell

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.200903527

      Thumbnail image of graphical abstract

      Recycling to a different TEMPO: An extremely simple and economic synthesis of a recyclable 2,2,4,4-tetramethylpiperdine-1-oxyl(TEMPO)-coated superparamagnetic catalyst is described. The catalyst shows excellent performance in the rapid oxidation of primary and secondary benzylic and aliphatic alcohols by using oxygen and MnII/CuII or biphasic NaOCl/KBr conditions.

    18. Mesoporous Materials

      Chiral Mesoporous Organosilica Nanospheres: Effect of Pore Structure on the Performance in Asymmetric Catalysis (pages 12727–12735)

      Dr. Xiao Liu, Dr. Peiyuan Wang, Dr. Lei Zhang, Dr. Jie Yang, Prof. Dr. Can Li and Prof. Dr. Qihua Yang

      Article first published online: 17 SEP 2010 | DOI: 10.1002/chem.201000931

      Thumbnail image of graphical abstract

      Spheres of influence: (R)-(+)-Binol-functionalized chiral periodic mesoporous organosilicas (PMOs) with different pore structures and morphology are efficient catalysts for the asymmetric addition of diethylzinc to aldehydes. Nanospheres with a radiative 2D hexagonal channel arrangement show the highest activity and ee value of the chiral PMOs investigated (see picture; MOM: methoxymethyl ether, CTAB: cetyltrimethylammonium bromide).

    19. Asymmetric Catalysis

      Improved Catalysts for the Iridium-Catalyzed Asymmetric Isomerization of Primary Allylic Alcohols Based on Charton Analysis (pages 12736–12745)

      Luca Mantilli, David Gérard, Sonya Torche, Dr. Céline Besnard and Dr. Clément Mazet

      Article first published online: 15 SEP 2010 | DOI: 10.1002/chem.201001311

      Thumbnail image of graphical abstract

      Achieving enantioselectivity: An improved generation of chiral cationic iridium catalysts for the asymmetric isomerization of primary allylic alcohols is disclosed. The design of these air-stable complexes relies on preliminary mechanistic information and on Charton analyses using two preceding generations of iridium catalysts developed for this highly challenging transformation (see figure).

    20. Heterocycle Synthesis

      A General Synthesis of Alkenyl-Substituted Benzofurans, Indoles, and Isoquinolones by Cascade Palladium-Catalyzed Heterocyclization/Oxidative Heck Coupling (pages 12746–12753)

      Dr. Rosana Álvarez, Claudio Martínez, Youssef Madich, J. Gabriel Denis, Dr. José M. Aurrecoechea and Prof. Dr. Ángel R. de Lera

      Article first published online: 21 SEP 2010 | DOI: 10.1002/chem.201001535

      Thumbnail image of graphical abstract

      Cascade synthesis: Benzofuran-, indole-, and isoquinolone-type derivatives are prepared using consecutive Sonogashira and cascade Pd-catalyzed heterocyclization/oxidative Heck couplings from readily available 2-halo-substituted phenol, aniline, and benzamide substrates, alkynes and functionalized olefins (see scheme).

  9. Preview

    1. Top of page
    2. Cover Picture
    3. Inside Cover
    4. Graphical Abstract
    5. News
    6. Minireview
    7. Correspondence
    8. Communications
    9. Full Papers
    10. Preview
    1. You have free access to this content
      Preview: Chem. Eur. J. 43/2010 (page 12759)

      Article first published online: 28 OCT 2010 | DOI: 10.1002/chem.201090211

SEARCH

SEARCH BY CITATION