Chemistry - A European Journal

Cover image for Vol. 19 Issue 14

April 2, 2013

Volume 19, Issue 14

Pages 4373–4639

  1. Cover Pictures

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Concept
    6. Communications
    7. Full Papers
    1. You have free access to this content
      Cover Picture: A Fully Integrated Continuous-Flow System for Asymmetric Catalysis: Enantioselective Hydrogenation with Supported Ionic Liquid Phase Catalysts Using Supercritical CO2 as the Mobile Phase (Chem. Eur. J. 14/2013) (page 4373)

      Dr. Ulrich Hintermair, Dr. Giancarlo Franciò and Prof. Dr. Walter Leitner

      Version of Record online: 20 MAR 2013 | DOI: 10.1002/chem.201390045

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      Πάντα ρει (everything flows) Asymmetric catalytic transformation of low-volatility organic substrates at mild reaction temperatures is achieved through a continuous-flow process based on a chiral transition-metal complex in a supported ionic-liquid phase (SILP) with supercritical carbon dioxide (scCO2) as the mobile phase. In the contribution on page 4538 ff., W. Leitner et al. show how effective systems based on this principle can be developed in an integrated approach ranging from the molecular scale (catalyst structure), through the meso-scale (separation strategy) to the macro-scale (process scheme). (Illustration: www.luenenschloss-design.de).

    2. You have free access to this content
      Back Cover: Resolving Multiple Non-equivalent Metal Sites in Magnesium-Containing Metal–Organic Frameworks by Natural Abundance 25Mg Solid-State NMR Spectroscopy (Chem. Eur. J. 14/2013) (page 4644)

      Jun Xu, Dr. Victor V. Terskikh and Prof. Dr. Yining Huang

      Version of Record online: 20 MAR 2013 | DOI: 10.1002/chem.201390048

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      Multiple (four) nonequivalent magnesium sites with very similar local Mg environments in a Mg-containing metal–organic framework, microporous α-Mg3(HCOO)6, have been resolved by 25Mg natural-abundance triple-quantum magic-angle spinning (3QMAS) NMR spectroscopy at an ultrahigh magnetic field of 21.1 T. For more details, see the Communication by Y. Huang et al. on page 4432 ff.

  2. Graphical Abstract

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Concept
    6. Communications
    7. Full Papers
  3. News

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Concept
    6. Communications
    7. Full Papers
  4. Concept

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Concept
    6. Communications
    7. Full Papers
    1. Artificial Photosynthesis

      Coupling Photocatalysis and Redox Biocatalysis Toward Biocatalyzed Artificial Photosynthesis (pages 4392–4406)

      Sahng Ha Lee, Jae Hong Kim and Prof. Chan Beum Park

      Version of Record online: 21 FEB 2013 | DOI: 10.1002/chem.201204385

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      Nature versus man-made: Biocatalyzed artificial photosynthesis occurs through the coupling of redox biocatalysis and photocatalysis to mimic natural photosynthesis based on visible-light-driven regeneration of enzyme cofactors. Key design principles for reaction components, such as electron donors, photosensitizers, and electron mediators, are described for artificial photosynthesis involving biocatalytic assemblies.

  5. Communications

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Concept
    6. Communications
    7. Full Papers
    1. Polyoxometalates

      Three New Imidazole-Functionalized Hexanuclear Oxidovanadium Clusters with Exceptional Catalytic Oxidation Properties for Alcohols (pages 4408–4413)

      Baokuan Chen, Xianqiang Huang, Prof. Dr. Bo Wang, Zhengguo Lin, Jufang Hu, Yingnan Chi and Prof. Dr. Changwen Hu

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201203854

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      Cluster cat: Three new imidazole-functionalized neutral hexanuclear vanadium clusters have been prepared, one of which shows exceptional catalytic activity in the selective aerobic oxidation of alcohols (see scheme). Furthermore, these new polyoxovanadium clusters can be readily recycled and reused with unchanged catalytic activity. A plausible catalytic cycle is also proposed.

    2. Stereoselective Catalysis

      Expanding Insight into Asymmetric Palladium-Catalyzed Allylic Alkylation of N-Heterocyclic Molecules and Cyclic Ketones (pages 4414–4418)

      Nathan B. Bennett, Douglas C. Duquette, Dr. Jimin Kim, Dr. Wen-Bo Liu, Dr. Alexander N. Marziale, Dr. Douglas C. Behenna, Dr. Scott C. Virgil and Prof. Brian M. Stoltz

      Version of Record online: 27 FEB 2013 | DOI: 10.1002/chem.201300030

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      Eeny, meeny, miny … enaminones! Lactams and imides have been shown to consistently provide enantioselectivities substantially higher than other substrate classes previously investigated in the palladium-catalyzed asymmetric decarboxylative allylic alkylation. Several new substrates have been designed to probe the contributions of electronic, steric, and stereoelectronic factors that distinguish the lactam/imide series as superior alkylation substrates (see scheme). These studies culminated in marked improvements on carbocyclic allylic alkylation substrates.

    3. Biomimetic Synthesis

      A Microbial-Mineralization Approach for Syntheses of Iron Oxides with a High Specific Surface Area (pages 4419–4422)

      Naoki Yagita, Dr. Yuya Oaki and Prof. Hiroaki Imai

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201204333

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      Of minerals and microbes: A microbial-mineralization-inspired approach was used to facilitate the syntheses of iron oxides with a high specific surface area, such as 253 m2 g−1 for maghemite (γ-Fe2O3) and 148 m2 g−1 for hematite (α-Fe2O3). These iron oxides can be applied to electrode material of lithium-ion batteries, adsorbents, and catalysts.

    4. Total Synthesis

      Total Syntheses of Ainsliadimer B and Gochnatiolides A and B (pages 4423–4427)

      Dongliang Xia, Yu Du, Zhi Yi, Hao Song and Prof. Dr. Yong Qin

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201204292

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      Oh my goch: The total syntheses of ainsliadimer B and gochnatiolides A and B from α-santonin have been accomplished in 25 steps with approximately 1 % overall yield. A Diels–Alder reaction of natural dehydrozaluzanin C with a monomeric guaianolide derivative allows stereoselective assembly of a dimeric gochnatiolide-type skeleton with the required stereochemistry and preinstalled functionalities for the synthesis of dimeric ainsliadimer B and gochnatiolides A and B (see scheme).

    5. Spiro Compounds

      Assembly of Spirooxindole Derivatives Containing Four Consecutive Stereocenters by Using Cascade Reactions Catalyzed by an N-Heterocyclic Carbene (pages 4428–4431)

      Dr. Bing Zhou, Dr. Zhi Luo and Prof. Dr. Yuanchao Li

      Version of Record online: 6 MAR 2013 | DOI: 10.1002/chem.201203436

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      In-spiro-ational: Biologically important and synthetically challenging spirocyclopentaneoxindoles with four consecutive stereocenters, including one spiroquaternary stereocenter, have been constructed in good yields and diastereoselectivity by a cascade reaction catalyzed by an N-heterocyclic carbene (see scheme). This reaction also provides a new strategy to access highly unusual tricyclic oxindoles.

    6. NMR Spectroscopy

      Resolving Multiple Non-equivalent Metal Sites in Magnesium-Containing Metal–Organic Frameworks by Natural Abundance 25Mg Solid-State NMR Spectroscopy (pages 4432–4436)

      Jun Xu, Dr. Victor V. Terskikh and Prof. Dr. Yining Huang

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201300113

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      In a spin: Directly differentiating multiple Mg sites in Mg-containing MOFs by 25Mg solid-state NMR spectroscopy is very challenging at natural abundance. By performing 25Mg two-dimensional triple-quantum magic-angle spinning solid-state NMR experiments at a magnetic field of 21.1 T at natural abundance, four non-equivalent Mg sites with very similar local environments in α-Mg3(HCOO)6 were unambiguously resolved (see figure).

    7. Transfer Hydrogenation

      Selective Ruthenium-Catalyzed Transfer Hydrogenations of Nitriles to Amines with 2-Butanol (pages 4437–4440)

      Svenja Werkmeister, Christoph Bornschein, Dr. Kathrin Junge and Prof. Dr. Matthias Beller

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201204633

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      Transfer your hydrogen: Fast and general transfer hydrogenation of nitriles to form primary amines is possible with a homogeneous Ru/1,4-bis(diphenylphosphino)butane (DPPB) catalyst (see scheme). The use of 2-butanol as the hydrogen-transfer reagent is essential for the selective reduction of aromatic, heteroaromatic, and aliphatic nitriles with this system.

    8. Cycloaddition

      N-Heterocyclic Carbene Catalyzed [4+2] Cycloaddition of Nitroalkenes with Oxodienes (pages 4441–4445)

      Xiang-Yu Chen, Li-Hui Sun and Prof. Dr. Song Ye

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201204539

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      NHC catalysis: N-heterocyclic carbenes were found to be efficient catalysts for the unprecedented [4+2] cycloaddition of nitroalkenes and oxodienes, giving the corresponding dihydropyrans in good yield with good diastereoselectivity (see scheme). Deuteration experiment reveals that the reaction is possibly initiated by the addition of N-heterocylic carbene to nitroalkenes.

    9. Mesoporous Materials

      Synthesis of Highly Strained Mesostructured SrTiO3/BaTiO3 Composite Films with Robust Ferroelectricity (pages 4446–4450)

      Dr. Norihiro Suzuki, Mohamed B. Zakaria, Nagy L. Torad, Prof. Dr. Kevin C.-W. Wu, Dr. Yoshihiro Nemoto, Dr. Masataka Imura, Prof. Dr. Minoru Osada and Prof. Dr. Yusuke Yamauchi

      Version of Record online: 28 FEB 2013 | DOI: 10.1002/chem.201203421

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      A new class of highly stable ferroelectric material, that is, a mesostructured SrTiO3/BaTiO3 composite film, obtained by a surfactant-templated sol–gel method is reported. Due to the concave surface geometry and abundant hetero-interface between SrTiO3 (ST) and BaTiO3 (BT) phases, a large number of strains can be created in the composite film, thereby leading to dramatic enhancement of ferroelectric property (see scheme).

  6. Full Papers

    1. Top of page
    2. Cover Pictures
    3. Graphical Abstract
    4. News
    5. Concept
    6. Communications
    7. Full Papers
    1. Ionic Liquids

      Water-Free Rare-Earth-Metal Ionic Liquids/Ionic Liquid Crystals Based on Hexanitratolanthanate(III) Anion (pages 4452–4461)

      Shun-Ping Ji, Meng Tang, Prof. Dr. Ling He and Prof. Dr. Guo-Hong Tao

      Version of Record online: 7 MAR 2013 | DOI: 10.1002/chem.201300092

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      Rare earth going liquid: Eleven water-free rare-earth-metal ionic liquids, [Cnmim]3[La(NO3)6] (n=1, 2, 4, 6, 8, 12, 14, 16, 18; mim=1-alkyl-3-methylimidazolium) were synthesized through a simple and mild reaction in quantitative yield. The lanthanum nitrate complexes were fully characterized and are stable to heat and moisture. Four of them were found to be ionic liquid crystals with a smectic A liquid-crystalline phase (see figure).

    2. Thermodynamics

      Do Intrinsically Disordered Proteins Possess High Specificity in Protein–Protein Interactions? (pages 4462–4467)

      Dr. Yongqi Huang and Prof. Zhirong Liu

      Version of Record online: 21 FEB 2013 | DOI: 10.1002/chem.201203100

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      Specificity from disorder? Thermodynamic data and simulations showed that enthalpy–entropy compensation for disordered protein complexes was more complete than that for ordered protein complexes under interface mutations (see figure), which suggests that the interaction specificity of disordered proteins is lower than that of ordered proteins.

    3. Cycloaddition

      Diels–Alder and Retro-Diels–Alder Cycloadditions of (1,2,3,4,5-Pentamethyl)cyclopentadiene to La@C2v-C82: Regioselectivity and Product Stability (pages 4468–4479)

      Marc Garcia-Borràs, Dr. Josep M. Luis, Prof. Dr. Marcel Swart and Prof. Dr. Miquel Solà

      Version of Record online: 10 FEB 2013 | DOI: 10.1002/chem.201203517

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      Going retro: Computational analysis of the Diels–Alder cycloadditions of Cp and Cp* to different bonds of La@C2v-C82 was used to compare the regioselectivity of these reactions, as well as to understand the origin of the thermal stabilities of the La@C82Cp and La@C82Cp* adducts. The results show that the regioselectivity of the two cycloadditions is the same, which corrects the previous assumption of the regioselectivity of the Cp attack.

    4. Nanostructures

      Molecular Spoked Wheels: Synthesis and Self-Assembly Studies on Rigid Nanoscale 2D Objects (pages 4480–4495)

      A. Vikas Aggarwal, Dr. Stefan-S. Jester, Sara Mehdizadeh Taheri, Prof. Dr. Stephan Förster and Prof. Dr. Sigurd Höger

      Version of Record online: 18 FEB 2013 | DOI: 10.1002/chem.201203444

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      The wheel deal: By relying on an optimized modular synthesis, derivatives of a new molecular spoked-wheel structure were accessed on a several hundred milligram scale (see figure). The self-assembly behavior of these approximately 4 nm-sized nanodisks was also studied in detail by means of dynamic light scattering, small-angle X-ray scattering, and scanning tunneling microscopy.

    5. Nanocomposites

      Phthalocyanine-Sensitized Graphene–CdS Nanocomposites: An Enhanced Photoelectrochemical Immunosensing Platform (pages 4496–4505)

      Dr. Yong-Jie Li, Meng-Jie Ma, Dr. Gui Yin, Dr. Yong Kong and Prof. Jun-Jie Zhu

      Version of Record online: 18 FEB 2013 | DOI: 10.1002/chem.201203521

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      Immunosensing by nanocomposites: An electron-transfer system composed of organic/inorganic ternary composites was developed without impairing the respective donor–acceptor components. The hierarchical system exhibited a high photocurrent generation capability and was used to construct a photoelectrochemical biosensor for the ultrasensitive detection of prostate-specific antigen (see figure; ITO=indium tin oxide, CoTAPc=cobalt 2,9,16,23-tetraaminophthalocyanine, CB=conducting band, VB=valence band).

    6. Aggregate-Induced Emission

      Highly Emissive Boron Ketoiminate Derivatives as a New Class of Aggregation-Induced Emission Fluorophores (pages 4506–4512)

      Ryousuke Yoshii, Dr. Atsushi Nagai, Dr. Kazuo Tanaka and Prof. Yoshiki Chujo

      Version of Record online: 30 JAN 2013 | DOI: 10.1002/chem.201203703

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      Molecules in motion: A series of boron ketoiminate derivatives that exhibited efficient aggregation-induced emission (AIE) characteristics (in THF: ΦPL≤0.01; in the solid state: ΦPL=0.30–0.76) were synthesized (see figure). The results of investigations indicate that the AIE characteristics are derived from molecular motions of the boron-chelating rings with a boron[BOND]nitrogen bond.

    7. Macrocycles

      Hydrindacene-Based Acetylenic Macrocycles with Horizontally and Vertically Ordered Functionality Arrays (pages 4513–4524)

      Prof. Hidetoshi Kawai, Tatsuya Utamura, Erina Motoi, Tomoko Takahashi, Hiroyoshi Sugino, Manabu Tamura, Prof. Masakazu Ohkita, Prof. Kenshu Fujiwara, Takao Saito, Prof. Takashi Tsuji and Prof. Takanori Suzuki

      Version of Record online: 11 FEB 2013 | DOI: 10.1002/chem.201200716

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      In all directions: Horizontally and vertically ordered functional arrays around a macrocycle can be constructed through multidimensional modifications of the hydrindacene derivatives as a versatile scaffold (see figure).

    8. Protein Engineering

      Modification of a Small β-Barrel Protein, To Give Pseudo-Amyloid Structures, Inhibits Amyloid β-Peptide Aggregation (pages 4525–4531)

      Yuko Murakoshi, Dr. Tsuyoshi Takahashi and Prof. Dr. Hisakazu Mihara

      Version of Record online: 1 FEB 2013 | DOI: 10.1002/chem.201202762

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      Anti-aggregation: An engineered protein (IG11KK) that gives pseudo-amyloid structures by using insulin-like growth factor 2 receptor domain 11 (IGF2R-d11) as a scaffold effectively suppresses the aggregation of Alzheimer's amyloid β-peptide (Aβ; see figure).

    9. Total Synthesis

      Formal Total Synthesis of the Algal Toxin (−)-Polycavernoside A (pages 4532–4537)

      M. Sc. Lennart Brewitz, Dr. Josep Llaveria, Dr. Akira Yada and Prof. Alois Fürstner

      Version of Record online: 18 FEB 2013 | DOI: 10.1002/chem.201204551

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      Panopticum: A host of early and late transition-metal catalysts enabled a new entry into the potent algal toxin polycavernoside A. The chosen route features the arguably most advanced Evans–Tishchenko fragment-coupling process known to date, as well as a striking example of a ring-closing alkyne metathesis reaction in combination with a gold-catalyzed transannular hydroalkoxylation step.

    10. Homogeneous Catalysis

      A Fully Integrated Continuous-Flow System for Asymmetric Catalysis: Enantioselective Hydrogenation with Supported Ionic Liquid Phase Catalysts Using Supercritical CO2 as the Mobile Phase (pages 4538–4547)

      Dr. Ulrich Hintermair, Dr. Giancarlo Franciò and Prof. Dr. Walter Leitner

      Version of Record online: 5 MAR 2013 | DOI: 10.1002/chem.201204159

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      Πequation imageντα ρει (everything flows): Asymmetric catalytic transformation of low-volatility organic substrates at mild reaction temperatures is achieved through a continuous-flow process based on a chiral transition-metal complex in a supported ionic-liquid phase (SILP) with supercritical carbon dioxide (scCO2) as the mobile phase (see figure).

    11. Bioluminescence

      Bioluminescent Microcapsules: Applications in Activating a Photosensitizer (pages 4548–4555)

      Dr. Jie Zhao, Dr. Jinbo Fei, Dr. Liang Gao, Wei Cui, Dr. Yang Yang, Dr. Anhe Wang and Prof. Dr. Junbai Li

      Version of Record online: 21 FEB 2013 | DOI: 10.1002/chem.201203922

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      Mobile light: Bioluminescent microcapsules containing D-luciferin were fabricated by using the covalent assembly of firefly luciferase (fLuc) and alginate dialdehyde (ADA) through a layer-by-layer (LBL) technique (see scheme). The microcapsules can produce visible light in the region of 520–680 nm after adding adenosine triphosphate (ATP), and activate photosensitizers without extra excitation.

    12. Photoluminescent Films

      Fixed-Component Lanthanide-Hybrid-Fabricated Full-Color Photoluminescent Films as Vapoluminescent Sensors (pages 4556–4562)

      Jun Xu, Dr. Lei Jia, Nengzhi Jin, Yufei Ma, Xiao Liu, Wenyu Wu, Prof. Weisheng Liu, Prof. Yu Tang and Prof. Feng Zhou

      Version of Record online: 29 JAN 2013 | DOI: 10.1002/chem.201204061

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      Color us impressed: Full-color photoluminescent films were fabricated facilely with a new fixed-component Ln-based hybrid. The tunable photoluminescence emissions of the films were achieved by changing the concentrations of OH in the hybrid and excitation wavelength, thus representing a new paradigm for full-color displays (see figure). The film can be used as a vapoluminescent sensor.

    13. Multicomponent Reactions

      The homo-PADAM Protocol: Stereoselective and Operationally Simple Synthesis of α-Oxo- or α-Hydroxy-γ-acylaminoamides and Chromanes (pages 4563–4569)

      Dr. Fabio Morana, Dr. Andrea Basso, Prof. Dr. Renata Riva, Valeria Rocca and Prof. Luca Banfi

      Version of Record online: 12 FEB 2013 | DOI: 10.1002/chem.201300023

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      A straightforward and fully stereoselective access to α-hydroxy-γ-acylaminoamides, α-oxo-γ-acylaminoamides, and chromanes is achieved by exploiting a sequence of: 1) an asymmetric organocatalytic Mannich reaction; 2) a Passerini multicomponent reaction; 3) an amine deprotection–acyl migration protocol; and 4) a final oxidation or cyclization. The whole sequence can be performed without purification of the intermediates.

    14. Calixarenes

      Using Calixarenes To Model Polyelectrolyte Surfactant Nucleation Sites (pages 4570–4576)

      Dr. Nuno Basilio, Borja Gómez, Prof. Luis Garcia-Rio and Vitor Francisco

      Version of Record online: 10 FEB 2013 | DOI: 10.1002/chem.201203377

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      Of micelles and mixtures: The addition of surfactant to a mixed micelle (composed of calixarene and cationic surfactant) leads to an increase in the concentration of free monomers once all the calixarene has been incorporated into the micelles (see figure). This behavior is contrary to that of pure micelles and resembles nucleation on polyelectrolyte–surfactant systems.

    15. Density Functional Calculations

      Oxygen-Assisted Hydroxymatairesinol Dehydrogenation: A Selective Secondary-Alcohol Oxidation over a Gold Catalyst (pages 4577–4585)

      Dr. Antonio Prestianni, Dr. Francesco Ferrante, Dr. Olga A. Simakova, Prof. Dario Duca and Prof. Dmitry Yu. Murzin

      Version of Record online: 5 FEB 2013 | DOI: 10.1002/chem.201202957

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      Reaction rates revealed: Open questions on the experimental findings concerning the relative rates of the 7-hydroxymatairesinol (HMR, two diastereomers depicted) secondary-alcohol oxidative dehydrogenation over an Au/Al2O3 catalyst are thoroughly answered by DFT calculations.

    16. NMR spectroscopy

      You have full text access to this OnlineOpen article
      Detection of Potential TNA and RNA Nucleoside Precursors in a Prebiotic Mixture by Pure Shift Diffusion-Ordered NMR Spectroscopy (pages 4586–4595)

      Dr. Saidul Islam, Dr. Juan A. Aguilar, Dr. Matthew W. Powner, Dr. Mathias Nilsson, Prof. Dr. Gareth A. Morris and Prof. Dr. John D. Sutherland

      Version of Record online: 1 FEB 2013 | DOI: 10.1002/chem.201202649

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      Complex to clear: An outwardly complex mixture, arising from mixing glycolaldehyde and cyanamide, was analysed by pure-shift DOSY NMR spectroscopy (see scheme). Amongst the species identified were potential threose nucleic acid (TNA) and RNA nucleoside precursors. These observations may have implications for the potentially prebiotic assembly chemistry of pyrimidine threonucleotides, and therefore of TNA.

    17. Enzyme Inhibition

      Telomerase Inhibitors from Cyanobacteria: Isolation and Synthesis of Sulfoquinovosyl Diacylglycerols from Microcystis aeruguinosa PCC 7806 (pages 4596–4601)

      Dr. Malika Makhlouf Brahmi, Dr. Cyril Portmann, Danilo D'Ambrosio, Dr. Tom M. Woods, Damiano Banfi, Patrick Reichenbach, Laeticia Da Silva, Emilie Baudat, Dr. Gerardo Turcatti, Prof. Dr. Joachim Lingner and Prof. Dr. Karl Gademann

      Version of Record online: 31 JAN 2013 | DOI: 10.1002/chem.201203296

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      Out in the green! Screening cyanobacteria for inhibitors of telomerase led to the identification of sulfoquinovosyl diacylglycerols as the active species (see figure). A structure–activity relationship study highlighted the importance of the lipid chains for the inhibition of telomerase, and a certain length was found to be essential for biological activity.

    18. Energetic Materials

      Synthesis of 5-Aminotetrazole-1 N-oxide and Its Azo Derivative: A Key Step in the Development of New Energetic Materials (pages 4602–4613)

      Dennis Fischer, Prof. Dr. Thomas M. Klapötke, Davin G. Piercey and Dr. Jörg Stierstorfer

      Version of Record online: 18 FEB 2013 | DOI: 10.1002/chem.201203493

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      A valued customer: The figure shows one frame of a high-speed movie of the combustion of azo-bis(1-hydroxytetrazolate). This compound shows high detonation and deflagration parameters and is valuable for the synthesis of new energetic materials.

    19. Lithiation

      Preparation of Stereodefined Secondary Alkyllithium Compounds (pages 4614–4622)

      Stephanie Seel, Dr. Guillaume Dagousset, Dr. Tobias Thaler, Annette Frischmuth, Prof. Dr. Konstantin Karaghiosoff, Prof. Dr. Hendrik Zipse and Prof. Dr. Paul Knochel

      Version of Record online: 10 FEB 2013 | DOI: 10.1002/chem.201204076

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      Love the way you Li/I: A stereoretentive iodine/lithium-exchange process allows the stereodefined preparation of cis- and trans-cycloalkyllithiums from their corresponding diastereomerically pure iodides. Quenching with electrophiles offers access to both cis- (up to 96 %) and trans-cycloalkyl derivatives (up to 99 %). The formation of oligomeric cyclohexyllithium structures was pivotal for explaining the observed stereochemical preference.

    20. RNA Synthesis

      The 2-Cyano-2,2-dimethylethanimine-N-oxymethyl Group for the 2′-Hydroxyl Protection of Ribonucleosides in the Solid-Phase Synthesis of RNA Sequences (pages 4623–4632)

      Dr. Jacek Cieślak, Dr. Cristina Ausín, Dr. Andrzej Grajkowski and Dr. Serge L. Beaucage

      Version of Record online: 18 FEB 2013 | DOI: 10.1002/chem.201204235

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      Novel 2-RNA protection: The reaction of 2-cyano-2-methyl propanal with 2′-O-aminooxymethylribonucleosides leads to 2′-O-(2-cyano-2,2-dimethylethanimine-N-oxymethyl)ribonucleosides, which were then converted into their fully protected phosphoramidite derivatives (see scheme; DMTr=4,4′-dimethoxytrityl). These amidites were successfully employed in the solid-phase synthesis of three chimeric RNA sequences, each with a different purine/pyrimidine ratio. This approach is straightforward, efficient, and cost effective.

    21. Fluorescent Probes

      DNAzyme-Based Probes for Telomerase Detection in Early-Stage Cancer Diagnosis (pages 4633–4639)

      Dr. Hui Wang, Michael J. Donovan, Dr. Ling Meng, Dr. Zilong Zhao, Dr. Youngmi Kim, Prof. Mao Ye and Prof. Weihong Tan

      Version of Record online: 20 FEB 2013 | DOI: 10.1002/chem.201204440

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      All's well that ends well: A PCR-free, DNAzyme-based telomerase sensor is demonstrated. Duplex formation between the PbII-specific DNAzyme fragment and telomere primer results in efficient and specific cleavage of telomere target after telomerase elongation (see figure). Our single-molecule probe design allows a quantifiable detection range from 0.1–1 μg total protein from cancer-cell lysate.

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