Angewandte Chemie International Edition in English

Cover image for Vol. 32 Issue 8

August 1993

Volume 32, Issue 8

Pages 1111–1222

Currently known as: Angewandte Chemie International Edition

    1. Cover Picture (Angew. Chem. Int. Ed. Engl. 8/1993)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311111

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      The cover picture refers to the Nobel review by R. A. Marcus on pages 1111–1121. The simplest chemical reaction—self-exchange electron transfer—is illustrated in the lower region with the reaction between green MnOmath image and violet MnOmath image, which in water occurs approximately 100 000 times per second. The potential function in the upper region illustrates a central point of the Marcus theory on the relation between the rate of an electron transfer reaction and its exothermicity: in very exothermic reactions an inverse region can occur, in which an increase of the free energy E correlates with a decrease in the reaction rate, that is, an increase in Ea. The pictures are taken from a poster, which was published by the Royal Swedish Academy of Science on conferment of the Nobel Prize in Chemistry.

  1. Reviews

    1. Top of page
    2. Reviews
    3. Highlights
    4. Communications
    5. Book Reviews
    1. Electron Transfer Reactions in Chemistry: Theory and Experiment (Nobel Lecture) (pages 1111–1121)

      Prof. Dr. Rudolph A. Marcus

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311113

      Extremely fruitful in many fields of chemistry, the theory Marcus developed in the fifties and sixties describes thermal electron transfer reactions. In his Nobel lecture, Marcus gives a short history of the development of the theory, mentions some of the predictions from it such as the occurrence of an inverted region for strongly exothermic reactions, and describes how some of these predictions have been confirmed by experiment.

    2. Protein Phosphorylation and Cellular Regulation I (Nobel Lecture) (pages 1122–1129)

      Prof. Edwin G. Krebs

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311221

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      It began at the start of the 1940s in the Cons' laboratory at Washington University in St. Louis: as a medical student Edwin Krebs participated in the investigations into phosphorylase, which had been found in two forms in the skeletal muscle of rabbits. Starting from the description of these findings—from which wrong conclusions had been drawn at the time—the two Nobel reviews present in a captivating way the complicated history of the research into protein phosphorylation. Today, it is known that many biochemical processes can be controlled by protein phosphorylation and dephosphorylation. The signal cascade is shown on the right, which effects the regulation of glycogenolysis by adrenaline (PK = protein kinase).

    3. Protein Phosphorylation and Cellular Regulation II (Nobel Lecture) (pages 1130–1137)

      Prof. Edmond H. Fischer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311301

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      It began at the start of the 1940s in the Cons' laboratory at Washington University in St. Louis: as a medical student Edwin Krebs participated in the investigations into phosphorylase, which had been found in two forms in the skeletal muscle of rabbits. Starting from the description of these findings—from which wrong conclusions had been drawn at the time—the two Nobel reviews present in a captivating way the complicated history of the research into protein phosphorylation. Today, it is known that many biochemical processes can be controlled by protein phosphorylation and dephosphorylation. The signal cascade is shown on the right, which effects the regulation of glycogenolysis by adrenaline (PK = protein kinase).

  2. Highlights

    1. Top of page
    2. Reviews
    3. Highlights
    4. Communications
    5. Book Reviews
    1. The Chemistry of the Fullerenes: An Overview (pages 1138–1141)

      Dr. Andreas Hirsch

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311381

      C60 is a chemical compound just like many others—this is the result of a large number of preparative reactions, which have been reported in the last few months. The selection presented here shows that C60 reacts, for example, as an olefin in [4 + 2], [3 + 2], and [2 + 1 ] cycloadditions. The preparative difficulties encountered at the beginning of fullerene research resulted in part from the hectic state of the initial burst of activity. After the “reign” of the physicists and physical chemists, it now appears to be the time of the preparative chemists.

    2. Prediction of the Secondary Structure of Proteins from the Amino Acid Sequence with Artificial Neural Networks (pages 1141–1143)

      Dipl.-Biochem. Gisbert Schneider and Priv.-Doz. Dr. Paul Wrede

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311411

      Secondary structures of amino acid sequences can be predicted with over 70% accuracy in Heidelberg with the aid of artificial neural networks. This improvement over the accuracy of statistical methods is extremely important in view of the rational design of peptides and proteins and the processing of data in sequence data banks. The potential of neural networks is thus demonstrated once again (see also the review “Neural Networks in Chemistry” by J. Gasteiger and J. Zupan in the April issue of Angewandte Chemie).

    3. Metal-Mediated Oxyfunctionalization of Organic Substrates by Organometallic Intermediates—More Recent Developments and Perspectives (pages 1144–1146)

      Dr. Jörg Sundermeyer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311441

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      Organometallic intermediates in polar oxygen-transfer reactions—an unrealistic proposition has become a certainty. This is one result of the research into the organometallic oxo and peroxo complexes, which has shown that the M[BOND]C bonds of MoVI, WVI, and ReVII Recomplexes can be stable under catalytic conditions. The precise mechanisms of the oxygen transfers are, however, still not known, and thus the very recent work by Herrmann et al. on Re catalysts such as 1 and by Sharpless et al. on OsO4 complexes should lead to more research in this area.

  3. Communications

    1. Top of page
    2. Reviews
    3. Highlights
    4. Communications
    5. Book Reviews
    1. Separation of the Enantiomers of 2,2′-Dihydroxy-1, 1′-binaphthyl and 10,10′-Dihydroxy-9,9′-biphenanthryl by Complexation with N-Alkylcinchonidinium Halides (pages 1147–1148)

      Associate Prof. Koichi Tanaka, Toru Okada and Prof. Fumio Toda

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311471

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      The separation of racemates of C2-symmetric biaryldiols, important starting materials for numerous ligands in asymmetric synthesis, can be achieved by using commercially available cinchonidinium halides 1, X = Cl, Br. In the first separation step inclusion complexes are formed from 1 and the diol; the alkyl substituent at the bridgehead N atom is decisive for the complexation behavior.

    2. Porphyries with Aromatic 26π-Electron Systems (pages 1148–1151)

      Dr. Thomas Wessel, Prof. Dr. Burchard Franck, Dr. Manfred Möller, Dipl.-Ing. Ute Rodewald and Mechthild Läge

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311481

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      Remarkably aromatic are the diaza[26]annulenes of type 1, which are stabilized by pyrrole rings positioned at the corners. This has been proven by 1H NMR spectroscopy, crystal structure analysis, and by electrophilic substitution reactions. In contrast, for the simple annulenes (CH)n, the aromaticity “stops” at the 22π electron system.

    3. Synthesis of 4-Deoxyaklanonic acid and Its Microbial Conversion into Anthracyclinones (pages 1151–1152)

      Prof. Dr. Karsten Krohn, Dr. Ernst Roemer, Michael Top and Dr. Christina Wagner

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311511

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      With a mutant strain of Streptomyces galilaeus, a cinerubin producer, the unnatural 4-deoxyaklanoic acid 1 can be converted into the enantiomerically pure 4-deoxyaklavinones 2 and 3. Through this combination of chemical synthesis and multistep biotransformation, the preparation of glycosidic anthracyclines should be possible, for which improved antitumor properties are expected.

    4. Competing M[DOUBLE BOND]Ccarbonyl and M[DOUBLE BOND]Ccarbene Bonds: Cycloaddition to the Metal[BOND]Ccarbonyl Bond in η2-Thiocarbene Complexes (pages 1152–1154)

      Prof. Dr. Fritz R. Kreissl, Dipl.-Chem. Wolfgang Schütt, Dipl.-Chem. Josef Ostermeier and Dr. Eberhardt Herdtweck

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311521

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      New light on the reactivity of M[DOUBLE BOND]C and M[DOUBLE BOND]C[DOUBLE BOND]O double bonds in η2-thiocarbene complexes has been shed by the cycloaddition reaction of 1 with thin- and selenourea. In these reactions not the M[DOUBLE BOND]Ccarbene bond, but for the first time the M[DOUBLE BOND]Cco bond is attacked, leading to the formation of the spirocyclic compounds 2 (X = S) and 3 (X = Se).

    5. On the BO Bond Length in Oxadiboriranes (pages 1154–1155)

      Dr. Michael Bühl, Prof. Dr. Henry Frederick Schaefer III, Paul von Rague Schleyer and Priv.-Doz. Dr. Roland Boese

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311541

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      The moral of the story: when the experimental results do not agree with those of high-level ab initio calculations, experimentalists are encouraged to consider other possible interpretations. Based on precise calculations on oxadiboriranes 1 ac, it became clear that for the X-ray structure analysis of 1 d a different refined model than the one originally published provides the “correct” structure.

    6. A Highly Electrophilic Unsaturated Ditungsten Dication (pages 1156–1157)

      Lda. M. Angeles Alvarez, Dr. M. Esther García, Prof. Dr. Victor Riera, Dr. Miguel A. Ruiz, Dr. Claudette Bois and Prof. Dr. Yves Jeannin

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311561

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      Through hydride or fluoride abstraction, the dication 1 reacts with BH3 · THF (PFmath image) to give monocationic complexes in which a hydrido (fluoro) ligand bridges a W[BOND]W triple bond (W[BOND]W single bond). The unusually high electrophilicity of 1 arises from the combination of positive charge and metal–metal multiple bond. The counterion in each case is PF6.

    7. Methyltrioxorhenium(VII) as Catalyst for Epoxidations: Structure of the Active Species and Mechanism of Catalysis (pages 1157–1160)

      Prof. Dr. Wolfgang A. Herrmann, Richard W. Fischer, Wolfgang Scherer and Monika U. Rauch

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311571

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      Explosive in the solid state, the bis(η2-peroxo) complex 1, which in solution is the active species in the epoxidation of olefins with [CH3ReO3], could be characterized by X-ray crystallography as the diglyme adduct 2. Under catalytic conditions (excess of H2O2), 1 is far more stable than in the free state.

    8. Golcondane: A Novel, Caged, Nonacyclic C20H24-Hydrocarbon of D2d Symmetry (pages 1160–1161)

      Prof. Goverdhan Mehta and S. Hari Krishna Reddy

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311601

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      In only five steps the title compound 1 can be synthesized from a bisnorbornenobenzoquinone. Intermediates en route to 1 may provide access to other interesting polycycles, for example to cyclic 1,4-tetramers of 1,3-cyclopentadiene such as 3. Golcondane 1 can be considered as a dieter of 2 or a product of a double intramolecular [2 + 2] cycloaddition of 3.

    9. Decamercuration of Ruthenocene (pages 1161–1163)

      Prof. Dr. Charles H. Winter, Young-Hee Han, Dr. Robert L. Ostrander and Prof. Dr. Arnold L. Rheingold

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311611

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      The reaction of [Cp2Ru] with Hg(OAc)2 in dichloroethane under reflux affords the complex 1 in 88% yield. The corresponding decahalo-substituted complexes (Cl, Br, I) can be prepared readily from 1 by reaction with CuCl2, KBr3, and KI3 (from KX and X2), respectively.

    10. Synthesis and Structure of a Diphospha[4]radialene (pages 1163–1165)

      Dr. Kozo Toyota, Katsuya Tashiro and Prof. Dr. Masaaki Yoshifuji

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311631

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      Diphospha[4]radialene 1 is planar and highly symmetrical in the crystal, and accessible from the corresponding 1,2-dibenzyl-substituted cyclobutene by bromination and debromination. The UV/VIS spectra of 1 indicate an extended π-electron system. Ar = 2,4,6-tBu3C6H2.

    11. Molecular Self-Organization of Amphotropic Cyanobiphenyl Mesogens (pages 1165–1167)

      Dr. Detlev Joachimi, Dr. habil. Carsten Tschierske, Henning Müller, Prof. Dr. Joachim Heinz Wendorff, Ludolf Schneider and Ralf Kleppinger

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311651

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      Do hydrogen bonds influence the behavior of the phases of amphiphilic “cyanobiphenyls”? Diol 1 forms, for example, a nematic mesophase. By the addition of H2O or the incorporation of further OH groups, the parallel movement of the molecules is hindered, and a smectic layer structure is induced.

    12. The “Phosphonioyl(phosphoranediyl)carbene” [(iPr2N)2P(H)CP(NiPr2)2]+ as a Source of New 1,3-Diphosphaallene Ylides: The First Carbodiphosphoranes with P[BOND]H Bonds (pages 1167–1169)

      Michèle Soleilhavoup, Dr. Antoine Baceiredo and Dr. Guy Bertrand

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311671

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      1,2-Hydrogen shifts in H-substituted carbodiphosphoranes 1 and 2 lead finally to an alkylidenephosphorane and a diphosphinomethane, respectively. Compounds 1 and 2 are accessible from the title compound 3 (counterion CF3SOmath image) by the reaction with NaBF4 and tBuLi, respectively. If, however, the proton is abstracted from 3 with tBuOK, the phosphaalkene 4 is formed.

    13. Complexation of Methane and Chlorofluorocarbons by Cryptophane-A in Organic Solution (pages 1169–1171)

      Dipl.-Chem. Laurent Garel, Dr. Jean-Pierre Dutasta and Prof. Dr. André Collet

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311691

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      Equivalent to a supercritical fluid is a description of the state of the methane molecule in the interior of the host cavity of a cryptophane molecule. The CH4–cryptophane complex (shown on the right) is amazingly stable even at room temperature (Ka = 130M−1), and its half-life is 6 μs. The findings of this study shed light on the bonding between neutral guest and neutral host molecules.

    14. [tert-Butylcyanide · Lithium Bis(trimethylsilyl)amide]2, a Model of the Intermediate RCN. MR′ Complex Formed in Reactions of Cyanides RCN with Organometallic Compounds R′M (pages 1171–1173)

      Prof. Dr. Gernot Boche, Ira Langlotz, Michael Marsch, Dr. Klaus Harms and Prof. Dr. Gernot Frenking

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311711

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      The dialkylation and dideuteration of cyanides are proposed to proceed through intermediates of the type RR′CHCN · LiR″. The title compound 1 (central framework shown on the right) is the first structurally characterized compound of this type. The results of ab initio calculations on the model compound H3CCN · LiNH2 are in agreement with the high stability and the energetically favorable intramolecular proton shift found experimentally.

    15. Domino Reactions of 4-Ene-1,2,3-triol Derivatives (pages 1173–1174)

      Prof. Dr. Johann Mulzer, Dipl.-Chem. Stefan Greifenberg, Dr. Jürgen Buschmann and Prof. Dr. Peter Luger

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311731

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      Proceeding through at least eight individual steps and ending with a dimerization, the domino cationic transformation of 1 leading to 2 provides a new synthetic approach to bis(furanosides). Domino processes are of current interest in organic synthesis, especially when the reaction requires many single steps and furnishes interesting products with high regio- and stereocontrol. a, R1 = H, R2= Me; b = R1 = R2 = H; c, R1 = Et, R2 = H.

    16. Diamino and Tetraamino Derivatives of Buckminsterfullerene C60 (pages 1174–1176)

      Dr. Klaus-Dieter Kampe, Dr. Norbert Egger and Dr. Martin Vogel

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311741

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      Mainly mono- and bisadducts are formed in the reaction of C60 with secondary diamines in toluene. The basic C60 derivatives can be obtained in pure form. Elemental analyses and NMR and mass spectra indicate that these monoadducts have the structure 1; thus, the addition of the diamine is apparently followed by a dehydrogenation. R1, R2 are for example CH3.

    17. A Catalytic Enantioselective Michael Addition of a Simple Malonate to Prochiral α,β-Unsaturated Ketoses and Aldehydes (pages 1176–1178)

      Prof. Dr. Masahiko Yamaguchi, Tai Shiraishi and Prof. Dr. Masahiro Hirama

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311761

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      Enantiomeric excesses of up to 77% ee can be achieved in the Michael addition of diisopropyl malonate to enones and enals in the presence of 5 mol % of the rubidium salt of L-proline (which contains a small amount of water) as catalyst. The absolute configurations of the products show that the nucleophile always attacks from the same side of the C[BOND]O plane irrespective of the configuration of the C[BOND]C bond.

    18. A Novel Mixed-Valence Tetranuclear VII/VIII Complex Isolated from 3,5-Di-tert-Butylcatechol/Vanadium(II)/Sodium Methoxide System for Dinitrogen Reduction (pages 1178–1179)

      Dr. Nataly P. Luneva, Svetlana A. Mironova, Prof. Alexander E. Shilov, Prof. Mikhail Yu. Antipin and Prof. Yuri T. Struchkov

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311781

      Vanadium centers octahedrally surrounded by oxygen atoms are found in the crystals of the title compound 1. This mixed-valent complex can be isolated from the N2-reducing system dbcat/VCl2/NaOCH3 in methanol after the catalytic activity has ceased. The structure of 1 supports the conjecture that multinuclear complexes participate in N2-reducing systems in protic media. dbcat = 3,5-di-tert-butylcatechol.

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    19. The First Neutral Adamantanoid Iron(III)-chelate Complex: Spontaneous Formation, Structure, and Electrochemistry (pages 1179–1182)

      Prof. Dr. Rolf W. Saalfrank, Dipl.-Chem. Bernd Hörner, Dr. Dietmar Stalke and Priv.-Doz. Dr. Josef Salbeck

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311791

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      “Metalloautism”—this term perfectly describes the characteristic of the adamantanoid iron(III) chelate complex 1 that the four iron centers do not interact with each other either electronically or magnetically. The four metal atoms are linked by six chelating ligands (2), which are prepared by deprotonation of the product of the condensation of terephthaloyl chloride and dimethyl malonate.

    20. Dilithiation of Two Diphenyl Ethers Each Containing Two NHCH2CH2Y (Y = OMe, NMe2) Side Arms in ortho Positions: Assembly of “Adamantanoid” Li4O2N4 Cores (pages 1182–1184)

      Ian Cragg-Hine, Matthew G. Davidson, Dr. Oldrich Kocian, Dr. Francis S. Mair, Ehmke Pohl, Dr. Paul R. Raithby, Dr. Ronald Snaith, Dr. Neil Spencer and Prof. J. Fraser Stoddart

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311821

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      No N2Li2 units are formed on dilithiation of the RNH-substituted ethers 1 and 2. Instead, the dimerization of two monomers leads to adamantanoid structures with Li4O2N4 frameworks and CH2CH2OMe and CH2CH2NMe2 side arms that are crucial for dimer formation. The adamantanoid structure of the Li2 compound prepared from 1 also persists in solution.

    21. Polymeric Hemiporphyrazines, a New Class of Rodlike Macromolecules Suitable for the Langmuir–Blodgett Technique (pages 1184–1187)

      Andreas Ferencz, Roland Ries and Prof. Dr. Gerhard Wegner

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311841

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      Out of the square form of the alkoxy-substituted hemiporphyrazinatogermanoxane 1 (R1 = CH3, R2 = C8H17) a new molecular architecture arises. The previously known rodlike molecules used for the LB technique all possess cylindrical symmetry.

    22. Tetrakis(trialkylsilylethynyl)butatriene and 1,1,4,4-Tetrakis(trialkylsilylethynyl)-1,3-butadiene: Novel Cross-Conjugated Chromophores (pages 1187–1189)

      Dr. Jan-Dirk van Loon, Paul Seiler and Prof. François Diederich

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311871

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      The first tetraethynyl[3]cumulene derivatives 2 have been prepared from 1 and structurally characterized by X-ray analysis. The central butatiene double bond is the most reactive site in 2 and can be selectively reduced by triphenylphosphane in the presence of water to form the strongly fluorescing 1,1,4,4-tetraethynyl-1,3-butadiene. Rhodium(I) also undergoes complexation at the central cumulene double bond. R = SiMe3, SiiPr3.

    23. The Absolute Configuration of Michellamine B, a “Dimeric”, Anti-HIV-Active Naphthylisoquinoline Alkaloid (pages 1190–1191)

      Prof. Dr. Gerhard Bringmann, Dipl.-Chem. Rainer Zagst, Manuela Schäffer, Dr. Yali F. Hallock, Dr. John H. Cardellina II and Prof. Dr. Michael R. Boyd

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311901

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      Ruthenium-mediated oxidative degradation led to the elucidation of the absolute configuration of michellamine B (1), the most active representative of a new class of naturally occurring “dimeric” naphthylisoquinolinealkaloids. Based on the degradation products, D-alanine and the (R)-3-aminobutyric acid, and the fact that the relative configurations of the stereocenters and the axis within the two molecular “halves” is known, 1 is deduced to have a (1 R,3R,5M,1‴ R,3‴ R,5P) configuration.

    24. Novel Synthesis of Tetrasubstituted β-Lactones: The Use of Indium in the Electrochemically Supported Reformatsky Reaction (pages 1191–1193)

      Prof. Dr. Hans Schick, Dipl.-Chem. Ralf Ludwig, Dr. Karl-Heinz Schwarz, Chem.-Ing. Katharina Kleiner and Dr. Annamarie Kunath

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311911

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      Not the anticipated β-hydroxycarboxylic acid esters but β-lactones 1 were obtained when ethyl 2-bromo-2-methylpropanoate and ketones were electrolyzed at a sacrificial indium anode. This is the first observation of the formation of β-lactones in the Reformatsky reaction. R1 and R2 can be, for instance, (CH2)5, 2Et, 2nBu, or 2Ph.

    25. Transformation of the First Zirconocene Alkyne Complex without an Additional Phosphane Ligand into a Dinuclear σ-Alkenyl Complex by Hydrogen Transfer from η5-C5H5 to the Alkyne Ligand (pages 1193–1195)

      Dr. habil. Uwe Rosenthal, Dipl.-Chem. Andreas Ohff, Dr. habil. Manfred Michalik, Dr. Helmar Görls, Dr. Vladimir V. Burlakov and Prof. Vladimir B. Shur

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311931

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      The agostic interaction between the alkenyl CH groups and the Zr centers is the most notable feature of the dinuclear complex 1, which is formed from the alkyne complex [Cp2Zr(thf)(Me3SiC[TRIPLE BOND]CSiMe3)] upon thermal loss of THF. In this transformation a H atom is transferred from the Cp ligand to the alkyne ligand.

    26. Host–Guest Complexes between Calix[4]arenes Derived from Resorcinol and Alkylammonium Ions (pages 1195–1197)

      Dipl.-Chem. Tino Lippmann, Prof. Dr. Horst Wilde, Dipl.-Chem. Maren Pink, Dr. Andrea Schäfer, Prof. Dr. Manfred Hesse and Prof. Dr. Gerhard Mann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311951

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      Electrospray mass spectrometry was used to detect stable host–guest complexes composed of cup-shaped calix[4]arenes 1 derived from resorcinol and straight-chain trialkylammonium ions in the gas phase. The crystal structure of 1 · (Et3HN)2SO4 consists of alternating hydrophobic and hydrophilic layers.

    27. Selective Dehydrogenation of Aldonic and Aldaric Acid with an R-Configurated α-Carbon Atom to 2-Oxocarboxylic Acids, and Reduction of the Oxo Group of N-Acetylneuraminic Acid with Proteus mirabilis (pages 1197–1198)

      Dr. Carsten Schinschel and Prof. Dr. Helmut Simon

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311971

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      An incredibly broad spectrum of substrates and electron acceptors are tolerated by the enzyme (2R)-hydroxycarboxlate-viologen-oxidoreductase (El). When the reaction is conducted with anthraquinone 2,6-disulfonate (AQDS) as the electron acceptor and dimethyl sulfoxide reductase (E2), (2R)-configurated aldonic/aldaric acids are dehydrated with complete selectivity. The reverse reaction, the reduction of 2-oxocarboxylic acids such as N-acetylneuraminic acid is also possible.

    28. A Self-Replicating System from Three Starting Materials (pages 1198–1201)

      Dipl.-Chem. Thomas Achilles and Prof. Dr. Günter von Kiedrowski

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199311981

      The reaction scheme may resemble a circuit diagram, but it actually represents a self-replicating system consisting of a trimeric, a dimeric, and a monomeric building block. The trimeric to hexameric deoxynucleotide derivatives arise in the presence of a carbodiimide and exhibit catalytic, cross-catalytic, and autocatalytic template effects that feed back into the various synthesis pathways. The major product is a tetramer that is formed preferably in a nonautocatalytic reaction path. In the autocatalytic pathway this product is exclusively “egoistic”, whereas the pentamer and hexamer enter into an “altruistic” relationship and “socialize” (i.e. thus behave as a molecular ensemble).

    29. Metallomesogens with a Cholesteric Mesophase (pages 1201–1203)

      Dr. Maria J. Baena, Julio Buey, Prof. Dr. Pablo Espinet, Dr. Heinz-S. Kitzerow and Prof. Dr. Gerd Heppke

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312011

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      The combination of thiolato and carboxylato bridges in 1 force a cis arrangement of the imine ligands unique for this type of complex. The chiral Binuclear complexes 1 are mesogenic and in nematic solvents induce cholesteric phases having a temperature-dependent helical screw sense. R′ is for example C6H13.

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    30. Improved Properties of Ferroelectric Liquid Crystals from Palladium β-Diketone Complexes (pages 1203–1205)

      María Jesús Baena, Dr. Pablo Espinet, Dr. María Blanca Ros, Dr. José Luis Serrano and Dr. Amaya Ezcurra

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312031

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      Switching times 1000-times faster and transition temperatures 50 K lower than those of the first mesogenic palladium complexes characterize the palladium complexes 1 (n =10, 14) reported here. Thus, applications may also become possible for ferroelectric liquid crystals from metallomesogens.

    31. 1,3-Bis(triphenylphosphoranylidene)allene and Tribenzyl(4-methyldiphenylphosphonio-butadiynyl)borate, Stabilized C3 and C4: Confirmation of a Hypothesis (pages 1205–1208)

      Prof. Dr. Hans Jürgen Bestmann, Dipl.-Chem. Dariusch Hadawi, Dr. Harald Behl, Dr. Matthias Bremer and Dipl.-Chem. Frank Hampel

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312051

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      “Naked” C3 and C4 units can be stabilized in 1 and 2, as predicted, by two triphenylphosphane molecules as donors and by a methyldiphenylphosphane donor and a tribenzylborane acceptor, respectively, at the ends of the carbon chains

    32. [{(Me3Si)2N}2Sm{μ(η88-C8H8)}-Sm{N(SiMe3)2}2]: An Inverse Organolanthanoid Sandwich Complex (pages 1208–1210)

      Prof. Dr. Herbert Schumann, Dr. Jörn Winterfeld, Dr. Lothar Esser and Dr. Gabriele Kociok-Köhn

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312081

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      Two amidosamarium units sandwich the planar cyclooctatetraene (cot) ligand in the title compound 1; this compound, the first example of an inverse-sandwich complex with a 4f metal, is accessible from [(cot)Sm(μ-Cl)(thf)2] and the appropriate sodium amide. Analogous reactions with Y, Gd, Er, and Lu compounds lead only to half sandwich complexes.

    33. Investigation of the Surface Structure of the Zeolites FAU and EMT by High-Resolution Transmission Electron Microscopy (pages 1210–1213)

      Viveka Alfredsson, Tetsu Ohsuna, Osamu Terasaki and Jan-Olov Bovin

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312101

      Thumbnail image of graphical abstract

      Almost atomic resolution is achieved in images of the surface structures of zeolites obtained by electron microscopy, as demonstrated in studies of synthetic faujasite (FAU, shown on the right) and its hexagonal polymorph EMT. In contrast, the surface of a dealuminated form of zeolite Y was shown to be coated with an amorphous layer. The steps found on the crystal surface allow conclusions concerning crystal growth to be drawn.

    34. C[BOND]H-Activation by Reaction of (Butadiene)zirconocenes and -hafnocenes with 9-BBN (pages 1213–1215)

      Prof. Dr. Gerhard Erker, Dipl.-Chem. Ralf Noe, Doris Wingbermühle and Prof. Dr. Jeffrey L. Petersen

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312131

      Thumbnail image of graphical abstract

      The simultaneous effects of a boryl substituent and a metallocene unit on a butadiene ligand can lead to C[BOND]H activation of this simple organic compound: Heating the complexes (1) formed from the relevant (butadiene)metallocene and 9-borabicyclo[3.3.1]nonane (9-BBN) affords complexes 2 (M = Zr) or, by the elimination of H2, 3 (M = Zr, Hf). R = H, Me.

  4. Book Reviews

    1. Top of page
    2. Reviews
    3. Highlights
    4. Communications
    5. Book Reviews
    1. Book Review: Science as Writing. By D. Locke (page 1221)

      Pierre Laszlo

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199312211

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