Angewandte Chemie International Edition in English

Cover image for Vol. 28 Issue 2

February 1989

Volume 28, Issue 2

Pages 135–252

Currently known as: Angewandte Chemie International Edition

    1. Cover Picture (Angew. Chem. Int. Ed. Engl. 2/1989)

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901351

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      The cover picture shows a trefoil knot, the topology of which has been realized for the first time in a “low molecular weight” compound. An 86-membered macroheterocycle containing 14 oxygen and 8 nitrogen atoms---with a molecular weight of 1690!---has this structure in solution, as shown by NMR studies. Whereas the isomeric, unraveled macrocycle exhibits a well-resolved, relatively easily interpretable 1H NMR spectrum, the molecular trefoil knot gives a spectrum displaying broad, poorly resolved signals in the arene region. Compounds with knot topologies are of considerable theoretical interest and have long intrigued chemists. Details on the synthesis and properties of these new molecular trefoil knots are reported by C. 0. Dietrich-Buchecker and J.-P. Sauvage on p. 189 ff.

    2. Graphical Abstract (Angew. Chem. Int. Ed. Engl. 2/1989)

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901352

  1. Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. Reaction Mechanisms in Heterogeneous Catalysis; C[BOND]H Activation as a Case Study (pages 135–145)

      Prof. Dr. Wilhelm F. Maier

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901353

      Organometallic chemistry was previously unable to make significant contributions to the understanding of classical heterogeneous catalysis, so important in industrial chemistry—this is the provocative thesis of this article. It attempts to illustrate, on the basis of mechanistic studies on C[BOND]H bond formation and activation in the presence of hydrogen, the progress made in understanding the mechanisms of heterogeneous catalysis. Unsolved problems are also mentioned.

    2. Biosynthetic Studies on Antibiotics (pages 146–177)

      Prof. Heinz G. Floss and Prof. John M. Beale

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901461

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      The intricacies of the chemical syntheses employed by living cells in the construction of complex organic natural products such as boromycin 1 can be studied in detail by stable-isotope labeling experiments in conjunction with highly developed methods of 2D NMR analysis. The “cryptic” stereo-chemistry of biosynthetic reactions can be uncovered by stereospecific isotope labeling. New possibilities are offered by molecular-biological techniques such as the analysis of blocked mutants and the cloning of “biosynthetic genes”, that is, the genes coding the enzymes involved in a biosynthetic pathway.

  2. Communications

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. Gas Chromatographic Determination of the Enantiomeric Composition of Epoxy Alcohols (pages 178–179)

      Prof. Dr. Wilfried A. König, Dipl.-Chem. Sabine Lutz, Dr. Gerhard Wenz, Dipl.-Chem. Günther Görgen, Dipl.-Chem. Christoph Neumann, Dipl.-Biol. Andreas Gäbler and Prof. Dr. Wilhelm Boland

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901781

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      Enantiomeric excesses greater than 98% can now be determined exactly in the synthesis of chiral epoxy alcohols. Capillary chromatography on peralkylated cyclodextrins allows the trifluoroacetyl derivatives of epoxy alcohols such as (E)-2,3-epoxy-4-octynol (picture on the right) and 2,3-epoxypropanol to be separated into their enantiomers within a few minutes.

    2. Tellurobenzaldehyde by Staudinger-Chalcogenation of the Ylide Benzylidenetriphenylphosphorane (pages 179–180)

      Prof. Dr. Gerhard Erker and Dipl.-Chem. Regina Hock

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901791

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      The ylide Ph3P[DOUBLE BOND]CHPh 1 and elemental tellurium react at 105°C in toluene to afford in situ tellurobenzaldehyde 2. Compound 2 is trapped with 2,3-dimethylbutadiene to form 3 and reacts with 1 to give stilbene; 2 is the first telluroaldehyde to be prepared in free form. The authors suggest the term “Staudinger-chalcogenation” for this method of synthesis.

    3. The Solid-State Structure of Me2B[BOND]O[BOND]BMe2 (pages 180–181)

      Dipl.-Chem. Horst Borrmann, Prof. Dr. Arndt Simon and Prof. Dr. Heinrich Vahrenkamp

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901801

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      An unexpected isosteric relationship with allenes was found for the diboroxane 1, which exists as a centrosymmetric dimer instead of as a linear monomer at −160°C. However, its structural parameters compare well with those calculated for dimeric allele. The tendency of 1 to dimerize may be due to the high Lewis acidity of boron and the high Lewis basicity of oxygen in diboroxanes as well as to the small substituents.

    4. Ethynol: Photochemical Generation in an Argon Matrix, IR Spectrum, and Photoisomerization to Ketene (pages 181–183)

      Dipl.-Math. Remo Hochstrasser and Prof. Dr. Jakob Wirz

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901811

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      Ethynol (“hydroxyacetylene”) 2 has been considered as a possible constituent of interstellar clouds, planetary atmospheres, and flames. Compound 2 was generated photochemically from 1 and investigated both spectroscopically and kinetically. The observed photoisomerization to the more stable tautomeric ketene 3, however, is evidence against an appreciable presence of 2 in interstellar space.

    5. Well-Resolved ESR Spectra of Arenecarboxyl Radicals in Solution (pages 183–185)

      Dr. Hans-Gert Korth, Dipl.-Chem. Wolfgang Müller, Dr. Janusz Lusztyk and Dr. Keith U. Ingold

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901831

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      The cleavage of benzoyl peroxide and its derivatives to radicals 1 in solution by UV photolysis at low temperature has made it possible, for the first time, to obtain high-resolution ESR spectra of these radicals in solution. The ESR coupling parameters show a preferred interaction of the unpaired electron localized primarily on oxygen with the atoms or groups in the ortho position; that is, σ radicals are present in the ground state. Thus, a through-space interaction is likely.

    6. Octabromocyclohexaarsenate, [As6Br8]2⊖ (pages 185–186)

      Prof. Dr. Ulrich Müller and Dr. Heike Sinning

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901851

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      The first perhalogenated cyclopolyarsane, the ion [As6Br8]2⊖, is formed in the reaction of PPh4[As2SBr5] with [Cr(CO)5(thf)], whereby arsenic is reduced. The mechanism of this reaction is still unclear. Formally, [As6Br8]2⊖ is an As6Br6 molecule having a chair conformation of the As6 ring with Br ions above and below the ring.

    7. The Structure of a C-Borylborirene with Strong C[BOND]B Hyperconjugation (pages 186–187)

      Dipl.-Chem. Andrea Höfner, Dipl.-Chem. Bernd Ziegler, Prof. Dr. Werner Massa and Prof. Dr. Armin Berndt

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901861

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      The geometric consequences of C[BOND]Y hyperconjugation in an uncharged system Y[BOND]C[BOND]X (shortening of the CX bond, lengthening of the CY bond, decrease in the YCX angle) were revealed by carrying out an X-ray structure analysis of the C-borylborirene 1. The structural parameters are in surprisingly good agreement with those obtained for orthogonal 2 by ab initio calculations (Dur = 2,3,5,6-tetramethylphenyl).

    8. Bromoselenates(II,IV), a Novel Type of Mixed Valence Compounds (pages 187–189)

      Prof. Dr. Bernt Krebs, Dr. Erhard Lührs and Dipl.-Chem. Frank-Peter Ahlers

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901871

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      The SeII and SeIV centers in the anions 1–3 are distinct. These anions were obtained from SeBr4 and bromides with bulky cations in weakly polar solvents. The SeII centers are coordinated in a square-planar fashion, the SeIV centers in an octahedral fashion. These structures are exemplified by 3 (below right), which, in addition, displays a short SeII-SeII distance. The formulas of the anions 1-3 are given below in the corresponding salts 1a-3a.

    9. A Synthetic Molecular Trefoil Knot (pages 189–192)

      Dr. Christiane O. Dietrich-Buchecker and Dr. Jean-Pierre Sauvage

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901891

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      Molecular knots have long been the subject of speculation. Now, for the first time, it has been possible to synthesize a “knotted” molecule having the topological chirality of a trefoil knot. Compound 1 was synthesized via a double-helix complex by exploiting the template effect of CuI ions. The chirality of 1 could be demonstrated by 1H NMR spectroscopy. The “unraveled” topological isomer of 1 was also synthesized.

    10. Temperature Dependent Inversion of Elution Sequence in the Resolution of α-Amino Acid Enantiomers on Chiral Diamide Selectors (pages 192–194)

      Dr. Katsunori Watabe, Rosita Charles and Prof. Dr. Emanuel Gil-Av

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901921

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      Great caution should be taken in attempting to derive configurations from the sequence of elution of enantiomers, according to the observations of Gil-Av et al. and Schurig et al. Both groups found a temperature dependence in the elution sequence obtained in the gas-chromatographic separation of enantiomers on chiral stationary phases, which led to lack of separation at the isoenantioselective temperature Tiso. defined by (a) and to a reversed order of elution above and below T.iso. Hydrogen-bond-forming systems (amino acids on diamide phases) and complex-forming selectand-selector systems (oxaspirocyclic compounds on nickel complexes) were investigated. The Tiso values were 130–150°C and 70–90°C, respectively. These findings show, at the same time, that below Tisothe elution sequence is determined by the differences in the interaction enthalpy as given by the Gibbs–Helmholtz equation (b) and that above Tiso it is determined by the interaction entropy.

    11. Evidence for a Temperature Dependent Reversal of the Enantioselectivity in Complexation Gas Chromatography on Chiral Phases (pages 194–196)

      Prof. Dr. Volker Schurig, Dipl.-Chem. Joachim Ossig and Dr. Rainer Link

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901941

      Thumbnail image of graphical abstract

      Great caution should be taken in attempting to derive configurations from the sequence of elution of enantiomers, according to the observations of Gil-Av et al. and Schurig et al. Both groups found a temperature dependence in the elution sequence obtained in the gas-chromatographic separation of enantiomers on chiral stationary phases, which led to lack of separation at the isoenantioselective temperature Tiso. defined by (a) and to a reversed order of elution above and below T.iso. Hydrogen-bond-forming systems (amino acids on diamide phases) and complex-forming selectand-selector systems (oxaspirocyclic compounds on nickel complexes) were investigated. The Tiso values were 130–150°C and 70–90°C, respectively. These findings show, at the same time, that below Tisothe elution sequence is determined by the differences in the interaction enthalpy as given by the Gibbs–Helmholtz equation (b) and that above Tiso it is determined by the interaction entropy.

    12. Can Polystyrene be Optically Active? (pages 196–198)

      Prof. Dr. Günter Wulff and Dr. Pradeep K. Dhal

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901961

      The first synthesis of optically active polystyrene with [α]math image as large as −3.5°was achieved by using an optically active template compound (D-mannitol derivative containing two p-vinylphenylboronic acid groups). This compound was copolymerized with styrene. The copolymer contains p-dihydroxyboryl-substituted distyrene diads of defined configuration, which are separated by atactic polystyrene segments. Reduction of the B(OH)2 groups affords polystyrene. In such an arrangement, approximately 25% of the diad centers are stereogenic and chirotopic (asymmetric), thus contributing to the optical rotation of the molecule.

    13. A Polyhedral Oligogermane: 4,8-Dibromoocta-tert-butyltetracyclo[3.3.0.02,7.03,6]octagermane (pages 198–199)

      Prof. Dr. Manfred Weidenbruch, Fred-Thomas Grimm, Prof. Dr. Siegfried Pohl and Dipl.-Chem. Wolfgang Saak

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901981

      Reductive halogen elimination from 1 offers a surprisingly simple route to the polycyclic germane 2. Compound 2 is air-stable and decomposes above 400°C. Its C2 symmetry is revealed in the presence of only four NMR signals for the tert-butyl protons.

      • equation image
    14. Residual Enantiomerism and Chromatographic Resolution of a 1,1,2-Triarylalkene (pages 199–201)

      Dr. Silvio E. Biali, Prof. Dr. Zvi Rappoport, Prof. Dr. Albrecht Mannschreck and Nikola Pustet

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198901991

      Thumbnail image of graphical abstract

      A three-ring flip A⇄B is the isomerization mechanism of lowest activation enthalpy for triarylalkene propeller molecules. NMR studies on 1, for which this mechanism leads to a diastereomerization rather than an enantiomerization, gave a value of 79.5 kJ mol −1 for this process. After chromatographic separation of the enantiomers of 1, it was also possible to determine the activation enthalpy of its enantiomerization, which presumably occurs by a [β,β′] two-ring flip: 92.7 kJ mol−1.

    15. LiSrN[BOND]A Three Dimensional Structural Arrangement of Corner and Edge Sharing Orthorhombic Bipyramids, NLi2/2Sr4/4 (pages 201–202)

      Dr. Gerhard Cordier, Dipl.-Chem. Axel Gudat, Prof. Dr. Rüdiger Kniep and Prof. Dr. Albrecht Rabenau

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902011

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      The crystalline stoichiometric phase LiSrN is an isotype of the YCoC structural type, which was first determined in 1986 by X-ray powder methods. Thus, this very simple structural type is not limited to transition-metal carbides. The metal cations Li and Sr form an arrangement previously observed in the CsCl structure. The anions (inside the polyhedron) occupy the centers of opposite faces of the (compressed) cube. LiSrN contains extended chains of [LiN]2⊖, the N atoms of which achieve rhombic-pyramidal coordination by additional contacts to four Sr atoms.

    16. Intramolecular Diels–Alder Reaction of Vinylsulfonic Acid Esters (pages 202–203)

      Eva Bovenschulte, Dr. Peter Metz and Priv.-Doz. Dr. Gerald Henkel

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902021

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      The highly diastereoselective intramolecular Diels–Alder reaction of the vinylsulfonate esters of the hydroxyalkylfurans 1 (R = Me, Et, iPr) to give the sultones 2 occurs at room temperature. MNDO and MMPMI calculations indicate a thermodynamic control of the relative configurations of 2.

    17. Identification of [(OC)4Fe[BOND]Si(CH3)2·{(H3C)2N}3PO] as Intermediate in the Formation of Polysilanes from (H3C)2SiCl2 and [Na2Fe(CO)4] (pages 203–205)

      Dr. Christian Zybill, Dr. Dallas L. Wilkinson, Christian Leis and Dr. Gerhard Müller

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902031

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      The preparation of polysilanes is not only of practical importance but also of mechanistic interest. In the presence of [Na2Fe(CO)4], Me2SiCl2 can undergo polymerization. A silanediyl complex, the title compound 1, can be trapped from such reaction mixtures by addition of HMPT at −45°C. An X-ray structure analysis of 1 has been performed. Compound 1 can be transformed either thermally or photochemically into a polysilane.

    18. Bis[(cyclooctane-1,5-diyl)di(pyrazol-1-yl)borato]cobalt: a Polypyrazolylborate Complex with Two Agostic Hydrogen Bonds (pages 205–206)

      Dr. Swiatoslaw Trofimenko, Dr. Joseph C. Calabrese and Dr. Jeffery S. Thompson

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902051

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      The new ligand 1 makes possible C ⃛H ⃛Co interactions in a complex. The complex, the title compound [Co(1)2], was isolated from aqueous solution. The trick leading to pseudooctahedral coordination in [Co(1)2] is the incorporation of boron into the [3.3.1] bicyclic framework. Co is coordinated by two N (equatorial) and one H (apical) from each of the two ligands. The H is bonded to C-2 of the ring system.

    19. Structure, Deformation Electron Densities, Photoelectron Spectra, and Reactivity of 3,4-Dihydro-1H-cyclobuta[a]cyclopropa[d]benzene (pages 206–208)

      Dipl.-Ing. Dieter Bläser, Dr. Roland Boese, Dipl.-Chem. Waldemar A. Brett, Prof. Dr. Paul Rademacher, Dr. Harald Schwager, Dr. Amnon Stanger and Prof. Dr. K. Peter C. Vollhardt

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902061

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      One of the most highly strained compounds is the title compound 1. The X-ray structure analysis of 1 has now allowed a comparison of 1 with the two “partial structures” 2 and 3. Compound 1 reacts with the complex [(Me3P)2Ni(cod)] to give 4. Surprisingly, competition experiments revealed that 2 reacts faster with the complex than 1—a finding that can be explained theoretically.

    20. 2,4,6-Triisopropylphenylcopper, a New Tetranuclear Organocopper Aggregate with Unsymmetrically Bridging σ-π Bonded Aryl Ligands (pages 208–210)

      Dr. Dominique Nobel, Prof. Dr. Gerard van Koten and Dr. Anthony L. Spek

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902081

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      A propeller-like structure for the title compound 1 in the solid state is a result of the unsymmetrical coordination of the aryl ligands, each of which is σ-bonded to one Cu and π-bonded to another. This is a consequence of the steric demands of the isopropyl substituents and leads to the unexpectedly high reactivity of 1 toward electrophiles such as phenyl isocyanate, which inserts into the Cu[BOND]C bonds.

    21. Reactions of Mono- and Dinuclear Metal-Alkylidyne Complexes with Phosphaalkynes: C[TRIPLE BOND]P and C[TRIPLE BOND]Mo Metathesis (pages 210–211)

      Dr. Anthony F. Hill, Dr. Judith A. K. Howard, Thomas P. Spaniol, Prof. Dr. F. Gordon A. Stone and Dr. Jürgen Szameitat

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902101

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      The isolobal analogy between the fragments CR, P, and d5-ML5 suggested the reaction of tBuC[TRIPLE BOND]P with the Mo complex 1. Indeed, this reaction gave the metathesis product 2. The W complex 3 reacted with tBuC[TRIPLE BOND]P to give an adduct 4, which can be regarded as an Fe(CO)3-stabilized 1-phospha-3-tungstacyclobutadiene.

    22. Hexaarsabenzene as Complex Ligand (pages 212–213)

      Prof. Dr. Otto J. Scherrer, Dr. Helmut Sitzmann and Dr. Gotthelf Wolmershäuser

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902121

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      Complexes 1(R [DOUBLE BOND] Me, Et) are accessible both thermally and photochemically. The central As6 ring is a regular hexagon with bond lengths between those of As-As single and double bonds. The 1H NMR signals of the cyclopentadienyl Me groups are found at δ ≈ 0; this can be regarded as evidence of a ring-current effect of hexaarsabenzene.

    23. Pyrones as Substrates for Palladium–Catalyzed [4 + 3] Cycloadditions (pages 213–215)

      Prof. Barry M. Trost and Dr. Stephan Schneider

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902131

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      A novel reaction of pyrones was observed upon treatment with the palladium complex 1, a 4π-electron reagent. Whereas pyrones normally behave as 2π-electron substrates toward 4π-electron systems, they undergo [4 + 3] cycloaddition with 1 to give seven-membered ring compounds such as 2 and 3. A two-step mechanism for the cycloaddition is offered as an explanation for this behavior.

    24. Synthesis, Structure, and Reactivity of Diphosphenes having a cis-Configuration (pages 215–217)

      Prof. Dr. Edgar Niecke, Dipl.-Chem. Berthold Kramer and Martin Nieger

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902151

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      The basic skeletons of the cis- diphosphenes 3 are nearly C2-symmetric. Compounds 3, which are very stable in pure form, are obtained from the aminophosphanes 1 via the diphosphanes 2. The surprisingly short distance between the amine proton and the arene ring (ca. 270 pm) indicates a weakly attractive interaction, which may contribute to the stability of the cis configuration. In analogy to trans-diphosphenes, the cis-diphosphenes coordinate to metal complexes. R = tBu, adamantyl, CEt3, C6H2iPr3; aryl [DOUBLE BOND] C6H2tBu3.

    25. A Tetraborylphosphonium Ion with a Spiroheterocyclic Structure (pages 217–218)

      Dr. Matthias Driess, Dipl.-Chem. Pascal Frankhauser, Dr. Hans Pritzkow and Prof. Dr. Walter Siebert

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902171

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      The crystal structure of the cation 1 resembles a Maltese cross. It has planar C2B2P rings, it is the first compound with B[BOND]P bonds between λ54-P and λ33-B atoms, and its compounds with X [DOUBLE BOND] Cl, BPh4 are ionic both in the solid and in solution. Cation 1 is formed from RClB[BOND]CH[DOUBLE BOND]CH[DOUBLE BOND]BC1R and P(SiMe3)3. R [DOUBLE BOND] NiPr2.

    26. LiBH4(NaBH4)/Me3SiCl, an Unusually Strong and Versatile Reducing Agent (pages 218–220)

      Dr. Athanassios Giannis and Prof. Dr. Konrad Sandhoff

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902181

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      Amines can be obtained from amides, nitriles, and nitroalkenes, alcohols from carboxylic acids, and sulfides from sulfoxides in good yields by use of the reducing agent LiBH4/Me3SiCl. Even α-amino acids can be easily reduced to amino alcohols with retention of optical purity. Compounds 1, 3, and 5 are examples of starting materials; 2, 4, and 6 are the products obtained in yields of more than 90%.

    27. Enzymatic Synthesis of Selectively Protected Glycals (pages 220–221)

      Dr. E. Wolfgang Holla

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902201

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      High regioselectivity and good yields characterize the lipase-catalyzed syntheses of 1–3 as well as other glucal and galactal derivatives. The acyl group transfer used in the synthesis of 1 and 2 is based on the irreversible transesterification with the respective vinyl carboxylates. Compound 3 is formed with an unexpected regiochemistry by lipase-catalyzed ester cleavage of the corresponding triacetate.

    28. Bis(trifluoromethyl)sulfene (CF3)2C[DOUBLE BOND]SO2, Isolated as Adduct (pages 221–223)

      Dr. Uwe Hartwig, Dr. Hans Pritzkow, Dipl.-Chem. Klaus Rall and Prof. Dr. Wolfgang Sundermeyer

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902211

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      The C[BOND]S bond in 2 is hardly longer than a normal C[BOND]S double bond; 2 is the first adduct of a symmetrically substituted sulfene. It was obtained from the dithietane 1 and quinuclidine. In contrast, 3 reacts with quinuclidine to give the zwitterionic compound 4.

    29. Highly Selective Oxidations of Fe(CO)3-Cyclohexadiene Complexes: Synthesis of 4b,8a-Dihydrocarbazol-3-ones and the First Total Synthesis of Carbazomycin A (pages 223–225)

      Dr. Hans-Joachim Knölker, Dipl.-Chem. Michael Bauermeister, Dipl.-Ing. Dieter Bläser, Dr. Roland Boese and Jörn-Bernd Pannek

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902231

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      An approach to the synthesis of highly substituted carbazole derivatives such as 2 and 3 is provided by the iron complex 1. Depending on the reaction conditions, this compound undergoes stereoselective cyclization to give either the 4a,9a-dihydro-9H-carbazole 2 or the new, analogously substituted 4b,8a-dihydrocarbazol-3-one. This method allows the total synthesis of carbazomycin A 3. Compound 2 exhibits optical anisotropy, which can be understood in terms of crystal packing.

    30. 2-Chloro-2H-phosphirene/1-Chloro-1H-phosphirene Isomerization by [1,3]-Chlorine Shift (pages 225–226)

      Dipl.-Chem. Oliver Wagner, Michael Ehle and Prof. Dr. Manfred Regitz

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902251

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      The contrasting behavior of nitrogen and phosphorus is shown by the product of reaction (a). Whereas only the 2H isomers of azirines are known to be stable, the initial 2H products of this thermally induced carbene addition undergo [1,3] chlorine shift to afford the 1H isomers 1. The stability of 1 might be due to a decrease in its potentially antiaromatic character by non-planarity at phosphorus. Nucleophilic substitutions provide a large variety of functionalized phosphirenes from 1.

  3. Book Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
  4. Corrigenda

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. You have free access to this content
      Corrigendum (page 228)

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902281

  5. Editorial Essay

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. Advanced Materials R & D — Planning for the Future (pages 229–235)

      Dr. James Economy

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902291

  6. Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. Magneto-Optical Recording and Data Storage Materials (pages 235–241)

      Dr. Frans J. A. M. Greidanus and Dipl.-Phys. Stefan Klahn

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902351

  7. Research News

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
  8. Conference Report

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. Intermetallic Phases (pages 243–245)

      Gerhard Sauthoff

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902431

    2. Biomaterials, Bioelectronics … (pages 245–246)

      Norbert Hampp

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902451

    3. The 1988 Fall Meeting of the Materials Research Society in Boston (pages 246–247)

      Robert W. Cahn

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902461

  9. Conference Calendar

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    6. Editorial Essay
    7. Reviews
    8. Research News
    9. Conference Report
    10. Conference Calendar
    1. Conference Calendar (pages 247–252)

      Article first published online: 30 DEC 2003 | DOI: 10.1002/anie.198902471

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