Angewandte Chemie International Edition

Cover image for Vol. 42 Issue 7

February 17, 2003

Volume 42, Issue 7

Pages 703–837

    1. Cover Picture: Vesicles and Polymerized Vesicles from Thiophene-Containing Rod–Coil Block Copolymers (Angew. Chem. Int. Ed. 7/2003) (page 703)

      Dennis M. Vriezema, Johan Hoogboom, Kelly Velonia, Ken Takazawa, Peter C. M. Christianen, Jan. C. Maan, Alan E. Rowan and Roeland J. M. Nolte

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390194

      Enzymes in vesicles are able to catalyze the reaction with substrates that permeate the vesicle membrane. The cover picture shows a vesicle built up from a rigid-rod diblock copolymer that is filled with Candida antarctica lipase B enzymes. The thiophene groups in the polymer can be polymerized by the addition of a metal complex, which may result in conducting vesicle membranes thus creating new possibilities in the area of nanoreactors. Further information can be found in the Communication by A. Rowan, R. Nolte et al. on page 772 ff.

    2. You have free access to this content
      Naphtho[1,8-b,c]phosphete and 1,2-Diphosphaacenaphthene from the Reaction of 1,8-Dilithionaphthalene with RPCl2 (page 712)

      Tsutomu Mizuta, Tooru Nakazono and Katsuhiko Miyoshi

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390196

    3. Web Site: RNA: Two in One (page 714)

      Christian Hammann and Wolfgang Nellen

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390197

    4. Book Review: Modern Arene Chemistry. Edited by Didier Astruc (page 716)

      Siegfried R. Waldvogel

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390199

    5. New Catalyzed Three-Component Cycloadditions for the Synthesis of Eight-Membered Carbocycles (pages 718–720)

      Masahiro Murakami

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390200

      Thumbnail image of graphical abstract

      The sum always amounts to eight—Two new three-component [m+n+o] cycloadditions offer novel synthetic routes to eight-membered carbocycles (see scheme; m, n, o=4, 2, 2 or 5, 2, 1). The rhodium center serves as a template and brings three components into the necessary arrangement for the desired cycloaddition, thus enabling difficult-to-form eight-membered carbocyclic rings to be constructed in a single chemical operation with good atom economy.

    6. A Kaiser Wilhelm Institute for Cologne! Emil Fischer, Konrad Adenauer, and the Meirowsky Endowment (pages 722–726)

      Lothar Jaenicke and Frieder W. Lichtenthaler

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390201

      Thumbnail image of graphical abstract

      It had already been decided by Emil Fischer (left) and Konrad Adenauer (right), but in the end the Kaiser Wilhelm Institute for Physiology was not built in Cologne. The historical background as to why this happened is explained.

    7. Vancomycin Assembly: Nature's Way (pages 730–765)

      Brian K. Hubbard and Christopher T. Walsh

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390202

      Thumbnail image of graphical abstract

      All good things come in threes: The synthesis of amino acid monomers, their joining, and their cross-linking are the three phases into which the biosynthesis of glycopeptide antibiotics (here vancomycin (blue) bound to a peptide (orange and red) is shown) can be divided. The elucidation of the reaction mechanism offers fascinating opportunities to make accessible antibiotics with previously unknown properties.

    8. You have free access to this content
      A Microfluidic System for Controlling Reaction Networks in Time (pages 768–772)

      Helen Song, Joshua D. Tice and Rustem F. Ismagilov

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390203

      Thumbnail image of graphical abstract

      Millisecond mixing and transport with no dispersion are achieved by unsteady flows induced in droplets of about 60 pL that travel through winding microfluidic channels (top). Fluorescence can be used to monitor mixing (bottom) or measure reaction rates. In principle, arbitrarily complex reaction networks can be created by combining and splitting streams of such droplets.

    9. Vesicles and Polymerized Vesicles from Thiophene-Containing Rod–Coil Block Copolymers (pages 772–776)

      Dennis M. Vriezema, Johan Hoogboom, Kelly Velonia, Ken Takazawa, Peter C. M. Christianen, Jan. C. Maan, Alan E. Rowan and Roeland J. M. Nolte

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390204

      Thumbnail image of graphical abstract

      Spontaneous formation of vesicles in both organic solvents and water is observed for new rod–coil-type diblock copolymers containing thiophene groups. The thiophene groups located in the skin of the aggregates can couple to give polymerized vesicles (see picture and cover picture). The vesicles are capable of including enzymes, which results in catalytically active microreactors that are permeable to substrate molecules.

    10. Design and Synthesis of γ-Dipeptide Derivatives with Submicromolar Affinities for Human Somatostatin Receptors (pages 776–778)

      Dieter Seebach, Laurent Schaeffer, Meinrad Brenner and Daniel Hoyer

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390205

      Thumbnail image of graphical abstract

      A simple, designed, open-chain γ-dipeptide derivative (see picture; Nap=naphthyl), which contains only three amide bonds, can mimic the 14-amino acid peptide hormone somatostatin. Surprisingly, the highest affinities (KD≈0.5 μM) for human receptors are observed when the “mandatory” Trp and Lys side chains on the turn mimic carry bulky substituents.

    11. You have free access to this content
      Liquid-Crystal Templating of Conducting Polymers (pages 778–781)

      James F. Hulvat and Samuel I. Stupp

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390206

      Thumbnail image of graphical abstract

      Mimicking the texture and anisotropy of the template, birefringent conducting polymer films (see picture) have been obtained by electropolymerization of 3,4-ethyldioxythiophene (EDOT) within a hexagonal lyotropic liquid crystal. Using a self-assembled template to control molecular orientation in conducting polymers could enhance electronic and optical properties.

    12. Single Crystals of the Disubstituted Anthracene 9,10-(Ph2P[DOUBLE BOND]S)2C14H8 Selectively and Reversibly Detect Toluene by Solid-State Fluorescence Emission (pages 783–787)

      Zhaofu Fei, Nikolaus Kocher, Christian J. Mohrschladt, Heiko Ihmels and Dietmar Stalke

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390207

      Thumbnail image of graphical abstract

      Not π stacking but C[BOND]H⋅⋅⋅π-ring center interactions lead to the fluorescence emission observed for the first time from a heteromolecular excimer complex. In single crystals a toluene molecule is located perpendicular to a Ph2P(S)-disubstituted anthracene chromophore. This toluene complex fluoresces (see picture) but the benzene complex does not.

    13. Stereoselective Solid-Phase Synthesis of Chiral Piperidine Derivatives by Using an Immobilized Galactose Auxiliary (pages 787–790)

      Gernot Zech and Horst Kunz

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390208

      Thumbnail image of graphical abstract

      The fluoride-labile anchoring of a galactosylamine enabled the first stereoselective solid-phase combinatorial synthesis of didehydropiperidinones 1. The piperidine derivatives formed by asymmetric domino Mannich–Michael condensation at ambient temperature were isolated after cleavage from the polymeric support in high yield, diastereomeric ratio, and purity (Piv=pivaloyl=tBuCO).

    14. You have free access to this content
      A New Principle in Combinatorial Asymmetric Transition-Metal Catalysis: Mixtures of Chiral Monodentate P Ligands (pages 790–793)

      Manfred T. Reetz, Thorsten Sell, Andreas Meiswinkel and Gerlinde Mehler

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390209

      Thumbnail image of graphical abstract

      The right mix!: Surprisingly, the use of the mixture of two different chiral monodentate phosphorus ligands (e.g., a phosphonite/phosphite combination; see schematic representation; cod=1,5-cyclooctadiene) in Rh-catalyzed olefin hydrogenation leads to significantly higher enantioselectivities than in the case of the pure ligands themselves.

    15. Reactions of Triazacyclohexanes with CuCl2: Surprising Formation of a Dimer between Two [CuCl2] Ions with an Unsupported Cuprophilic Attraction (pages 793–796)

      Randolf D. Köhn, Guido Seifert, Zhida Pan, Mary F. Mahon and Gabriele Kociok-Köhn

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390210

      Thumbnail image of graphical abstract

      Cuprophilic interactions are observed between the two copper centers of the unprecedented dimer 2, the structure of which contains two associated [CuICl2] ions. The surrounding complex is derived from the internal reduction of the CuII complex 1, which displays a cis-divacant octahedral coordination geometry.

    16. Small Circular Oligodeoxynucleotides Achieved from Self-Assembling Entities (pages 797–799)

      Dongsheng Liu, Jian Chen, Alex H. F. Lee, Larry M. C. Chow, Albert S. C. Chan and Tianhu Li

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390211

      Thumbnail image of graphical abstract

      Self-recognition rather than complementarity defines the self-assembly (a) of two cytosine-rich oligodeoxynucleotides in the compact i-motif shown (C[BOND]C+ base pairs, dark circles). When the 5′-terminal phosphate is activated, phosphodiester bonds form between the termini of the linear sequences, resulting in two circular oligodeoxynucleotides (b), which disassociate on denaturation (c).

    17. Creation of a Superhydrophobic Surface from an Amphiphilic Polymer (pages 800–802)

      Lin Feng, Yanlin Song, Jin Zhai, Biqian Liu, Jian Xu, Lei Jiang and Daoben Zhu

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390212

      Thumbnail image of graphical abstract

      Poly(vinyl alcohol), an inherently amphiphilic material, can act as a superhydrophobic surface when deposited as nanofibers on an aluminum oxide membrane (see picture). The arrangement of the hydrophobic and hydrophilic functional groups, both in the surface and within the interior of the material, has a marked effect on surface activity.

    18. Catalytic Functionalization of Hydrocarbons by σ-Bond-Metathesis Chemistry: Dehydrosilylation of Methane with a Scandium Catalyst (pages 803–805)

      Aaron D. Sadow and T. Don Tilley

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390213

      Thumbnail image of graphical abstract

      C–H activation with scandium: Reaction of [Cpequation imageScCH3] (1, Cp*=C5Me5) with MesSiH3 (Mes=2,4,6-C6H2Me3) yielded a new scandium silyl complex [Cpequation imageScSiH2Mes] (2) by an unusual σ-bond metathesis pathway. Complex 2 activates the C[BOND]H bonds of benzene and methane. In the presence of excess Ph2SiH2, the catalytic dehydrosilation of saturated and unsaturated hydrocarbons, including methane, was accomplished, with [Cpequation imageScH] (see scheme; R=CH3, C3H5, CH[DOUBLE BOND]CMe2) which can be formed from 1 or 2. This appears to be the first example of catalytic methane functionalization by σ-bond metathesis.

    19. The Palladium-Catalyzed Addition of Organoboronic Acids to Alkynes (pages 805–808)

      Chang Ho Oh, Hyung Hoon Jung, Ki Seong Kim and Nakjoong Kim

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390214

      Thumbnail image of graphical abstract

      No base is necessary: Excellent yields are produced on addition of organoboronic acids to alkynes under mild reaction conditions when palladium compounds are used as catalysts (see scheme). Unlike the Suzuki-type cross-coupling reaction, the current reaction occurs in an acidic medium.

    20. Why Trimerization? Computational Elucidation of the Origin of Selective Trimerization of Ethene Catalyzed by [TaCl3(CH3)2] and An Agostic-Assisted Hydride Transfer Mechanism (pages 808–811)

      Zhi-Xiang Yu and K N. Houk

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390215

      Thumbnail image of graphical abstract

      Because only then a relatively rapid agostic-assisted hydrogen shift can help to form the product. This is the answer to the question in the title and it results from a computational analysis of the catalytic cycle shown and its alternatives for dimerization, tetramerization, and higher oligomerization.

    21. A One-Pot Four-Component (ABC2) Synthesis of Macrocycles (pages 811–814)

      Pierre Janvier, Michèle Bois-Choussy, Hugues Bienaymé and Jieping Zhu

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390216

      Thumbnail image of graphical abstract

      Six bonds are generated in one pot with concomitant creation of two oxazole groups as part of a new macrocycle. Simply mixing a diamine (2) and an aldehyde (3; 1:2 molar ratio) in MeOH at room temperature, followed by addition of diisocyanoacetamide (4) and heating at reflux, provides symmetric cyclophanes in good yield.

    22. You have free access to this content
      The First Thorium Arene Complex: A Divalent Synthon (pages 814–818)

      Ilia Korobkov, Sandro Gambarotta and Glenn P. A. Yap

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390217

      Thumbnail image of graphical abstract

      A highly reactive thorium naphthalene complex, namely 1-[Li(dme)3] was prepared by reducing a ThIV precursor with Li(naphthalene). The complex behaves as a synthon for ThII and reacts with Me3SiN3 to give the thorium silazanate 2.

    23. Spiroannulation by Alkylation and Reductive Cyclization of Nitriles (pages 818–820)

      Scott D. Rychnovsky and Leo R. Takaoka

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390218

      Thumbnail image of graphical abstract

      A new ring-forming reaction has been developed in which nitriles act as 1,1-dianion synthons with biselectrophiles. The cyclizations are highly diastereoselective and are capable of forming two adjacent quaternary centers with complete selectivity (see scheme; LiDBB=lithium di-tert-butylbiphenylide).

    24. Single-Pot Conversion of Methane into Acetic Acid in the Absence of CO and with Vanadium Catalysts Such as Amavadine (pages 821–823)

      Patrícia M. Reis, José A. L. Silva, António F. Palavra, João J. R. Fraústo da Silva, Tsugio Kitamura, Yuzo Fujiwara and Armando J. L. Pombeiro

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390219

      Thumbnail image of graphical abstract

      Although its biological function is still unknown, the naturally occurring vanadium complex amavadine may be suitable for industrial applications: This compound (as well as other VIV and VV complexes with N,O and O,O ligands) are shown to act as catalysts for the direct conversion of methane into acetic acid, without requiring CO, under very mild conditions and in high yields (see scheme).

    25. Real-Time Chemical-Shift Scaling in High-Resolution NMR Spectroscopy (pages 823–825)

      Gareth A. Morris, Neil P. Jerome and Lu-Yun Lian

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390220

      Thumbnail image of graphical abstract

      Imitating a low-field spectrometer may seem a strange concept, but might be of great help to laboratories that no longer have access to such machines. For example, slowing down the average evolution of the chemical shift during NMR-signal acquisition changes the strength of coupling between spins and the effects of chemical exchange. The spectra of quinine shown were obtained with the NMR technique proposed here.

    26. From Alkenylsilanes to Ketones with Air as the Oxidant (pages 825–827)

      Junichi Kondo, Hiroshi Shinokubo and Koichiro Oshima

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390221

      Thumbnail image of graphical abstract

      Air and water are required for a tandem intermolecular radical addition–oxidation sequence that converts alkenylsilanes into a variety of ketones. The reaction of 2-silyl-1-alkenes with various carbon-centered radicals (see scheme) provides carbonyl compounds in good yields. This process represents a novel oxidative transformation of organosilicon compounds with molecular oxygen as the oxidant. R3Si=MePh2Si, Me2PhSi, R1=Me, Ph, CO2Me, SiMe2Ph, R2=CH2COR′ (R′=OBn, NEt2, OnBu, Ph), C6F13.

    27. Organic-Catalyst-Mediated Cyclopropanation Reaction (pages 828–831)

      Charles D. Papageorgiou, Steven V. Ley and Matthew J. Gaunt

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390222

      Thumbnail image of graphical abstract

      A catalytic ammonium ylide based cyclopropanation process forms trans-disubstituted cyclopropanes in good yield upon reaction with electron-deficient alkenes (see scheme; EWG=electron-withdrawing group). The reaction is also highly enantioselective when a stoichiometric amount of a chiral tertiary amine is used.

    28. Preview: Angew. Chem. Int. Ed. 7/2003 (page 837)

      Version of Record online: 17 FEB 2003 | DOI: 10.1002/anie.200390223

SEARCH

SEARCH BY CITATION