Angewandte Chemie International Edition in English

Cover image for Vol. 26 Issue 7

July 1987

Volume 26, Issue 7

Pages 595–706

Currently known as: Angewandte Chemie International Edition

    1. Cover Picture (Angew. Chem. Int. Ed. Engl. 7/1987)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198705951

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      The cover shows a model of the structure of a Cu2-complex with two peripheral 30-membered rings concatenated with a 44-membered central ring. The complex consists of two (phenanthroline)2Cu+ complexes which are easily recognizable by their Cu (purple) and N (blue). One phenanthroline ligand in each of the two complexes contains a phenylene-O-(CH2O)5-phenylene bridge; one of these ligands (with its bridge) is shown in green, the other in light brown (red: O). The two unbridged phenanthroline ligands are connected together by two “straight chains” (phenylene-O-CH2-C4-CH2-O-phenylene). These ligands and bridges (yellow) from the central ring of the Cu2-[3]-catenate. Further details of this fascinating globular molecule are reported by J.-P. Sauvage et al. on p. 661ff.

  1. Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Correspondences
    5. Book Reviews
    1. The Development of the Electron Microscope and of Electron Microscopy (Nobel Lecture) (pages 595–605)

      Prof. Dr. Ernst Ruska

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198705953

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      The lectures delivered in Stockholm by last year's receivers of the Nobel prize for Physics are of great interest for chemists since both electron- and scanning-tunneling microscopy are used in surface studies. The three laureates give colorful historical accounts of the development of their techniques without neglecting interesting human aspects—“some joyful events and many disappointments” (Ruska). One of the first highlights of scanning tunneling microscopy was the elucidation of the 7 × 7 reconstruction of the Si(111) surface, see picture.

    2. Scanning Tunneling Microscopy—from Birth to Adolescence (Nobel Lecture) (pages 606–614)

      Dr. Gerd Binnig and Dr. Heinrich Rohrer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706061

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      The lectures delivered in Stockholm by last year's receivers of the Nobel prize for Physics are of great interest for chemists since both electron- and scanning-tunneling microscopy are used in surface studies. The three laureates give colorful historical accounts of the development of their techniques without neglecting interesting human aspects—“some joyful events and many disappointments” (Ruska). One of the first highlights of scanning tunneling microscopy was the elucidation of the 7 × 7 reconstruction of the Si(111) surface, see picture.

    3. New Cisplatin Analogues—On the Way to Better Antitumor Agents (pages 615–624)

      Prof. Dr. Alessandro Pasini and Dr. Franco Zunino

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706151

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      The clinical success of cisplatin 1 in the chemotherapy of tumors encouraged a search for analogues with lower toxicity, better therapeutic index, and higher activity. Thus far, however, only very few of the “traditional” analogues have proven promising in clinical tests. The use of carrier, molecules or chemotherapeutics as ligands and/or of complexes with several Pt atoms could possibly lead to better results.

    4. Direct Identification of the Carbon Skeleton of Organic Compounds using Double Quantum Coherence 13C-NMR Spectroscopy. The INADEQUATE Pulse Sequence (pages 625–642)

      Priv.-Doz. Dr. Joachim Buddrus and Dr. Hans Bauer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706251

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      Couplings between 13C nuclei afford information directly on the carbon-carbon connectivities in the carbon skeleton, but, however, they were hitherto extremely difficult to observe because of the low natural abundance of 13C. It is now possible to use a special NMR pulse sequence to make such couplings more readily visible. For example, the constitution of the tricyclic ketone 1 (CO groups not shown) could be determined by two-dimensional INADEQUATE-13C-NMR spectroscopy.

    5. Biological Exploitation of Solar Energy by Photosynthetic Water Splitting (pages 643–660)

      Prof. Dr. Gernot Renger

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706431

      The splitting of water by solar radiation into oxygen and metabolically bound hydrogen during photosynthesis is of central importance for the existence of higher forms of life on earth. The oxygen thereby formed is a powerful oxidant which permits an energetically highly efficient nutrient turnover. In recent years considerable progress has been made in understanding the functional and structural organization of photosynthetic water splitting. This is especially true for the partial step of oxidation of water to O2.

  2. Communications

    1. Top of page
    2. Reviews
    3. Communications
    4. Correspondences
    5. Book Reviews
    1. Molecular Structure of a [3]-Catenate: Curling Up of the Interlocked System by Interaction between the Two Copper Complex Subunits (pages 661–663)

      Dr. Christiane O. Dietrich-Buchecker, Dr. Jean Guilhem, Dr. Abdel Kader Khemiss, Dr. Jean-Pierre Kintzinger, Dr. Claudine Pascard and Dr. Jean-Pierre Sauvage

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706611

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      Other than the formula would suggest, 12⊕ has a globular “tertiary structure” both in solution and in the solid state; this was revealed by NMR studies and an X-ray structure analysis, π-π interactions between aromatic subunits probably contribute to the stability of the tertiary structure of the Cu2-[3]-catenate (stacking arrangement).

    2. New Lead Structures by Diels-Alder Reactions of Streptazolin with Naphthoquinones (pages 664–665)

      Dr. Susanne Grabley, Dr. Heinz Kluge and Dr. Hans-Ullrich Hoppe

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706641

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      Striking antibiotic and cytotoxic properties are exhibited by the products 3 and derivatives thereof. Compounds 3 are obtained in good yields from the chiral diene streptazolin 1 (R3 [DOUBLE BOND] H) and naphthoquinones 2. The low endo-/exo-selectivity and diastereofacial selectivity of the cycloaddition are, by way of exception, an advantage; they make a number of isomers accessible for the screening of natural products. (R1, R2 [DOUBLE BOND] H, OH, OAc; R3 [DOUBLE BOND] H, Ac, SiMe2tBu.)

    3. The First Synthesis of a Benzoborole (pages 665–666)

      Dipl.-Chem. Wolfgang Schacht and Priv.-Doz. Dr. Dieter Kaufmann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706651

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      The flash vacuum pyrolysis of 1-chloro-1-boraindane 1 leads with dehydrogenation to the 1-benzoborole 2. The highly reactive, antiaromatic system dimerizes regiospecifically even at low temperatures to the diboradibenzotetrahydroazulene 3. Trapping reactions with 2-butyne. DCl and CH3OD furnished products which likewise suggest intermediary occurrence of 2.

    4. Vanadium Carbene Complexes by Reaction of (Diene)metallocenes with [CpV(CO)4] (pages 666–668)

      Prof. Dr. Gerhard Erker, Dipl.-Chem. Rainer Lecht, Dipl.-Chem. Rüger Schlund, Dr. Klaus Angermund and Prof. Dr. Carl Krüger

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706661

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      Despite their importance as potential intermediates, carbenevanadium complexes are still a rarity. Reaction of (butadiene)zirconocene or (butadiene)hafnocene with [CpV(CO)4] affords 1, which for M [DOUBLE BOND] Zr is in equilibrium with the reaction partners in solution, whereas for M [DOUBLE BOND] Hf it is in equilibrium with 2.

    5. Synthesis and Structure of a Cyclopropapyridine (pages 668–669)

      Dr. Ramesh Bambal, Prof. Dr. Hans Fritz, Grety Rihs, Dr. Théophile Tschamber and Prof. Dr. Jacques Streith

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706681

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      Selective excitation of the N [DOUBLE BOND] N π electrons of 1 led to the first cyclopropapyridine 3. Compound 3, which is presumably formed by ring closure from the diradical intermediate 2, is acid-labile, but seemingly stable in the crystalline state under argon (R [DOUBLE BOND] N[BOND]COPh).

    6. Synthesis and Structure of [(OC)4Fe [DOUBLE BOND]Si(OtBu)2·HMPT], a Donor-Stabilized Silanediyl (“Silylene”) Complex (pages 669–670)

      Dr. Christian Zybill and Dr. Gerhard Müller

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706691

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      The first stable silanediyl complex 1 is monomeric both in solution and in the crystalline state. 1 has a polar Si[DOUBLE BOND]Fe bond and is stabilized by adduct formation with hexamethylphosphoric triamide (HMPT). As expected, the silanediyl ligand occupies an apical position of the trigonal-bipyramidally coordinated iron atom.

    7. Proton-Controlled Equilibration between [4+ + 2] and [4 + 2+] Cycloadducts: A Characteristic Example for the Aberrant Diels-Alder Reactions between Two 1,3-Dienes (pages 670–672)

      Dr. Karin Beck and Prof. Dr. Siegfried Hünig

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706701

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      [4 + 2]-Cycloadducts of two different 1,3-dienes can be the result of a Diels-Alder reaction or a Diels-Alder reaction and subsequent Cope rearrangement. This duality is manifested in the mobile equilibria between 1-H, 2, 3, and 4-H. The rearrangement 3 + H [RIGHTWARDS ARROW] 4-H, a novel diaza-Cope rearrangement, is more rapid than the cycloreversion to 1-H and 2.

    8. Azo Cope Rearrangements of Nonstabilized Azo Compounds (pages 672–673)

      Dr. Karin Beck, Dr. Harald Burghard, Dipl.-Ing. Gabriele Fischer, Prof. Dr. Siegfried Hünig and Dipl.-Chem. Petra Reinold

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706721

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      The acid-catalyzed [4 + 2] cycloaddition of the cyclic azines 1 with the 1,3-dienes 2 leads to a mixture of the azo compounds 3 and the hydrazones 4.3 and 4 are interconverted by acid-catalyzed [3.3] rearrangement. The structural dependence of this novel Cope rearrangement corresponds to the energy differences of 3 and 4, which were estimated by force field calculations.

      X

    9. Redox Disproportionation of GeII Compounds: Synthesis and Structure of [(Me3Si)C(PMe2)2]2GeCl2 and [μ-{(Me3Si)C(PMe2)2}]2Ge2 (pages 673–674)

      Priv.-Doz. Dr. Hans H. Karsch, Dipl.-Chem. Brigitte Deubelly, Jürgen Riede and Dr. Gerhard Müller

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706731

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      A longer Ge[BOND]Ge bond than in polygermanes is found in the “bisgermanediyl” 1, which is thus in no way comparable with digermenes R2Ge[DOUBLE BOND]GeR2. The very stable Ge1 compound 1 with lone pairs at the Ge centers is formed upon reaction of GeCl2 with the phosphinomethanide [(Me3Si)(Me2P)2C] in excess.

    10. [{μ-[(Me3Si)C(PMe2)2]}2Ge2]2GeCl2, a Germanediyl-Donor Germanediyl-Acceptor Complex Containing a Mixed-Valent Ge5 Chain (pages 674–676)

      Priv.-Doz. Dr. Hans H. Karsch, Dipl.-Chem. Brigitte Deubelly, Jürgen Riede and Dr. Gerhard Müller

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706741

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      The title compound, a GeI-GeI-GeII-GeI-GeI polygermane is completely dissociated in solution at room temperature; in the solid state there is an almost linear GeCl2 moiety surrounded equatorially by two-ligands 1. The structure of the resulting angular Ge5 chain with the two Cl atoms is shown on the right.

      [μ-{(Me3Si)C(PMe2)2}]2Ge21

    11. The Morphology and Microstructure of Colloidal Silver and Gold (pages 676–678)

      D. G. Duff, A. C. Curtis, Dr. Peter P. Edwards, D. A. Jefferson, Dr. Brian F. G. Johnson, A. I. Kirkland and D. E. Logan

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706761

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      Colloid-chemically synthesized gigantic gold and silver clusters and microparticles have been investigated by high-resolution electron microscopy. In the case of the gold samples decahedral and icosahedral, multitwinned and triangular flattened particles were characterized. In the silver samples there were extremely small particles (<40 Å, see right-hand side of picture) whose structure is interpreted in terms of a pentagonal packing of the atoms. The inset shows a structural model (left, top) and a computer-simulated image (left, bottom).

    12. The Synthesis of 1,3- and 1,4-Phenylene-Linked Bisquinone-Substituted Porphyrin Dimers (pages 678–680)

      Prof. Jonathan L. Sessler and Martin R. Johnson

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706781

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      Structural studies of the photosynthetic reaction center (RC) have revealed that both donor-acceptor distances and inter-macrocycle orientations play a crucial role in mediating the photosynthetic charge separation process. Numerous photosynthetic model systems have already been synthesized and studied in an effort to understand the first of these factors, while intermacrocycle effects have not been thoroughly addressed in model systems. Models with various fixed angles between the porphyrin units have now been synthesized for the first time: the linear 1 and a “gable”-type analogue. Solutions of both compounds in toluene showed no detectable fluorescence when irradiated at 418 nm.

    13. Highly Polarizing Co2+ Ions from [Co2(CO)8] and Pyridine in Hydrocarbons: Synthesis and Structure of [{CO3(CO)10}2{Co(py)4}] and [(CO4CoCo(py)3][Co(CO)4] (pages 680–681)

      Prof. Giuseppe Fachinetti, Dr. Giovanni Fochi, Dr. Tiziana Funaioli and Prof. Pier Francesco Zanazzi

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706801

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      The two title compounds are a neutral complex and a homonuclear ion pair, respectively. The carmine-red Co7-complex consists of an octahedrally coordinated Co2+ central ion surrounded by four pyridine ligands and two [Co3(CO)10] clusters. The cation of the emerald-green Co3 complex has the structure 1.

    14. Alkylaluminum Cations: Synthesis and Structure of (pages 681–682)

      Dr. Lutz M. Engelhardt, Dr. Ulrich Kynast, Dr. Colin L. Raston and Dr. Allan H. White

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706811

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      A distorted tetrahedral environment, a bond length typical for terminal Al[BOND]C bonds, and unusually small Al[BOND]N distances characterize the cation 1, which is formed on addition of AlCl3 to the corresponding chloride. The Al[BOND]N distances show that Lewis acid-base interactions are required for the stabilization of a dialkylaluminum ion.

    15. Optically Active α-Arylglycine Esters by Friedel-Crafts Alkylation with the Chiral Cation of the Bislactim Ether of cyclo-(L-Val-Gly) (pages 683–684)

      Prof. Dr. Ulrich Schöllkopf, Dipl.-Chem. Sabine Grüttner, Dr. Ralf Anderskewitz, Dr. Ernst Egert and Michael Dyrbusch

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706831

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      The chiral non-racemic glycine cation equivalent 1 enabled the synthesis of the previously unknown methyl (R)-α-arylglycinate 3. The Friedel-Crafts adducts 2 could be hydrolyzed without epimerization or racemization with 2 equivalents of 0.1 N HCl. α-Arylglycines are of particular interest as pharmacophoric building blocks of drugs. (R1–R4 [DOUBLE BOND] H, OEt, OMe.)

    16. A Mixed-Metal Cluster with Two Quadruply-Bridging Carbonyl Ligands (pages 685–686)

      Prof. Richard D. Adams, James E. Babin and Dr. Miklos Tasi

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706851

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      A type of coordination important for cluster-surface analogy could be realized on two counts at one and the same time in the complex 1: the two μ4-CO ligands in 1 are so arranged that the C atoms each bridge a Ru2Mo triangle and the O atoms are additionally bound to a further Ru atom; the C[BOND]O distance is large (1.25(1) Å).

    17. Hydride Abstraction From [C6H6Os(CO)(CH3)2]: Does a Metal-bound Methyl Group Migrate Preferentially to a CO or to a CH2 Ligand? (pages 686–687)

      Dipl.-Chem. Karin Roder and Prof. Dr. Helmut Werner

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706861

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      To a CH2 Ligand! is the answer to the question posed in the title—an indirect confirmation of the concept already proposed by Fischer and Tropsch regarding the growth step of the synthesis bearing their names. The reaction was found to take place in the Os complex 1, from which an H ion can be split off. The ethene complex 3 is formed from the presumed intermediate 2 by CH3-migration and β-H shift.

    18. Square Hg4 Clusters in the Compound CsHg (pages 687–688)

      Prof. Dr. Hans-Jörg Deiseroth and Dipl.-Chem. Axel Strunck

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706871

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      The bonding situation in CsHg, which contains isolated, square-planar Hg4 clusters, lies between that of the two extremes (Cs)4(Hg4)4⊖ and (CsHg4)04e. The temperature dependence of the specific electrical resistance of this gold-bronze, extremely air-sensitive compound proves it to be a metal, so that the formulation with free electrons may be regarded as the more appropriate one. The picture on the right-shows a section of the crystal structure of CsHg (distances in ppm).

    19. Fcu[AuF4], an Unusual Copper(II) Fluoroaurate(III) (pages 688–689)

      Dr. Bernd G. Müller

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706881

      The title compound, a ternary fluoride of two coinage metals, has unusual composition, structure, and magnetic properties. The kind and extent of Jahn-Teller distortion for Cu2+ are unexpected; the coordination number for Cu2+ is 2 + 2 + 2 = 6, while gold, on the other hand, shows the usual squareplanar coordination for Au3+-compounds. The compound is antiferromagnetic; the one-dimensional, magnetic interaction takes place along the linear Cu-F chains parallel to [001].

    20. Ag[MF6]2 (M [DOUBLE BOND] Nb, Ta), Ternary fluorides of Divalent Silber (pages 689–690)

      Dr. Bernd G. Müller

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706891

      High-pressure fluorination (pmath image ≈ 3 kbar) of Ag2O/Ta2O3 mixtures afforded brilliant-blue single crystals of Ag[TaF6]2. The crystal structure is surprisingly simple: three isolated and noticeably elongated AgF6 octahedra are each coupled cis with one another above and below the (100) plane via TaF6 octahedra. The magnetic behavior—paramagnetism—is understandable, but F-bridges, through which magnetic interactions could take place, are lacking.

    21. Generation and Interception of 1-Oxa-3,4-cyclohexadiene (pages 690–692)

      Dr. Michael Schreck and Prof. Dr. Manfred Christl

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706901

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      The title compound 2 could be the most strained monocyclic allene. It is generated from 1 by reaction with n-butyllithium and can be trapped with a series of alkenes. Thus, with styrene the diastereomeric [2 + 2] adducts 3 are formed. 2 reacts with 1,3-dienes to give [2 + 2]- and [2 + 4]-adducts, and, in the absence of reactive partners, 3-n-butyl-2,4-pentadien-1-ol is formed from 2 upon addition of n-BuLi.

    22. Second Sphere Coordination of Tetraammineplatinum(II) by a Macropolycyclic Crown Ether Bisamide Receptor (pages 692–693)

      Dr. David R. Alston, Alexandra M. Z. Slawin, Dr. J. Fraser Stoddart, Dr. David J. Williams and Ryszard Zarzycki

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706921

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      Second sphere coordination of two receptor molecules to a metal complex has been observed for the macropolycycle 1. [Pt(NH3)4][PF6]2 forms discrete adducts with two molecules of 1; H-bridges between carbonyl[BOND]O and ether[BOND]O atoms on the one hand and NH3 on the other are crucial. Cisplatin does not form any adducts with 1.

    23. Macrobicyclic Polyethers as Second Sphere Ligands for Tetraammineplatinum(II) (pages 693–696)

      Dr. David R. Alston, Alexandra M. Z. Slawin, Dr. J. Fraser Stoddart, Dr. David J. Williams and Ryszard Zarzycki

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706931

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      A T-arrangement of two benzene rings contributes—aside from H-bridges—to the stabilization of a 2:1 adduct of the molecular receptor 2 with [Pt(NH3)4]2⊕ in the solid state (X-ray structure analysis); in [D6]acetone only a 1:1 adduct is present (1H-NMR). With the same cation, 1 forms only 1:1 adducts in solution and in the solid state. Thus, small changes in the ligands can drastically alter its bonding properties (1, R [DOUBLE BOND] H; 2, R [DOUBLE BOND] Me).

    24. Crystal Structure of the η1-Allyl-Grignard Compound Bis(allylmagnesium chloride-TMEDA) (pages 696–697)

      Michael Marsch, Dr. Klaus Harms, Priv.-Doz. Dr. Werner Massa and Prof. Dr. Gernot Boche

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706961

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      A good model for the structure or allyl-Grignard compounds in solution is the crystal structure of the title compound. Dimers are present—half of such a dimer is shown on the right—which are coupled via MgClMgCl four-membered rings. The C9-Mg distance is 217.9(3) pm and lies in the range of other C[BOND]Mg distances in alkyl-Grignard compounds. The C[BOND]C distances in the allyl group are different: C9-C10 = 144.2(4) and C10-C11 = 133.5(4) pm.

    25. Dinuclear Fulvalene Complexes of Tri- and Tetravalent Zirconium (pages 697–699)

      Prof. Dr. Wolfgang A. Herrmann, Dr. Tomás Cuenca, Dr. Babil Menjón and Dr. Eberhardt Herdtweck

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706971

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      The isomers 2 count among the few unequivocally characterized ZrIII-alkyl compounds. They were prepared from 1 and MeLi exploiting the fulvalene bracketing effect. Further functionalization of 1 without fragmentation has also been achieved.

    26. Precipitates with β-Pleated Sheet Structure by Mixing Aqueous Solutions of Helical Poly(D-lysine) and Poly(L-lysine) (pages 699–700)

      Prof. Dr. Jürgen-Hinrich Fuhrhop, Dipl.-Chem. Matthias Krull and Prof. Dr. Georg Büldt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198706991

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      The spontaneous transformation of soluble polypeptide helices into insoluble sheet structures upon combining the two enantiomeric helices (shown schematically in the picture on the right) implies that metastable superstructures have longevity in solution when they are made up of chiral subunits. On combining clear solutions of the title compounds, which are stable for weeks, the racemate immediately precipitates in almost quantitative yield. Apparently the extremely large surface areas (energies) due to the curvature of the helices impairs crystallization, whereas crystal planes without curvature can be formed in the racemate.

    27. Electron Delocalization in Diruthenium Complexes of Polycyclic Arenes (pages 700–702)

      Dr. Klaus-Dieter Plitzko and Prof. Dr. V. Boekelheide

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707001

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      A very rapid intramolecular two-electron transfer between Ru0 and RuII or a species with two RuI centers is the explanation given for the unusual properties of the cation of 1. 1H- and 13C-NMR spectra are highly symmetric, and further reduction to the Rumath image neutral complex first takes place at −1.177 ± 0.010 V (vs. SCE). The phenanthrene analogue of 1—one double bond more—behaves completely differently; it obviously contains an RuII center and an Ru0 center.

    28. Macrocyclic Dienes by Metathetic Dimerization of Cycloheptene and Cyclooctene on Re2O7/Al2O3 (pages 702–703)

      Prof. Dr. Siegfried Warwel, Dipl.-Chem. Hans Kätker and Claudia Rauenbusch

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707021

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      In a preparatively facile reaction with Re2O7/Al2O3 as catalyst and using the dilution principle in a Soxhlet-like recycling apparatus, the metathesis of cycloolefins, which normally leads to unsaturated polymers, can be steered to macrocycles. Cycloheptene, for example, is smoothly converted into 1,8-cyclotetradecadiene (selectivity 80%! yield 68%).

  3. Correspondences

    1. Top of page
    2. Reviews
    3. Communications
    4. Correspondences
    5. Book Reviews
    1. Correspondence (page 703)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707031

  4. Book Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Correspondences
    5. Book Reviews

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