Angewandte Chemie International Edition in English

Cover image for Vol. 33 Issue 14

August 2, 1994

Volume 33, Issue 14

Pages 1407–1522

Currently known as: Angewandte Chemie International Edition

    1. Cover Picture (Angew. Chem. Int. Ed. Engl. 14/1994)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414051

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      The cover picture shows the chemical formula of the tetraprotonated form of turcasarin, to date the largest expanded porphyrin. This class of compounds includes both macrocyclic porphyrin analogues and ring systems with more than four pyrrole units. The 40 π-electron annulene turcasarin exists as a pair of enantiomers in solution and in the solid state; the individual enantiomers adopt a nearly C2-symmetric, twisted “figure-eight” conformation. The interconversion of the two conformers via an open “circular” conformation (shown in the center of the picture) is slow on the NMR timescale at room temperature. More about this cyclic oligopyrrole, which in the tetraprotonated form, in analogy to several other expanded porphyrins, could serve as an anion binding and transport agent, is reported by J. L. Sessleret al. on p. 1509 ff.

  1. Reviews

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books
    1. Peptidyl-Prolyl cis/trans Isomerases and Their Effectors (pages 1415–1436)

      Prof. Dr. Gunter Fischer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414151

      The profound biological consequences of simple cis/trans isomerizations in the peptide chain and the complexity of the processes on the molecular level are evident from investigations of peptidyl-prolyl isomerases (PPIases), which have been known for only a few years. Two families of proteins among the PPIases have been identified along with several inhibitors and binding proteins. But much remains to be discovered.

    2. Conformational Requirements for Sweet-Tasting Peptides and Peptidomimetics (pages 1437–1451)

      Dr. Toshimasa Yamazaki, Prof. Dr. Ettore Benedetti, Darin Kent and Prof. Dr. Murray Goodman

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414371

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      An L-shaped conformation is responsible for the sweet taste of aspartame (1) and other dipeptides, according to NMR studies and computer simulations of 1 and twelve analogues. Since the conformations of the compounds are dominated by packing forces in the solid state, the X-ray crystal structures do not reflect the bioactive conformations.

  2. Highlights

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books
    1. Reactions in Supercritical Carbon Dioxide (pages 1452–1455)

      Prof. Dr. Gerd Kaupp

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414521

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      An efficient method for producing tasty beer: characteristic bittering agents such as trans-isohumulone (1) can be obtained readily by photolysis of the hops extract in supercritical CO2 in an established industrial process without large losses incurred on boiling. Nontoxic, environmentally friendly, cheap, nonflammable, and applicable on a large scale—these assets of supercritical CO2 have long been recognized for extractions; this highlight shows that supercritical CO2 is also advantageous for many reactions.

    2. Triple Bonds in Small Rings: Testing the Limits of Chemical Bonds (pages 1455–1456)

      Prof. Dr. Wolfram Sander

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414551

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      Mission Impossible? This is hardly true for the quest for small-ring alkynes. Maier et al. (Angew. Chem. Int. Ed. Engl.1994, 33, 1248) combined a new method of gas-phase pyrolysis with matrix isolation techniques to synthesize a three-membered ring compound with a C[TRIPLE BOND]C bond, the CH2Si isomer 3, from disilane 1 [Eq. (a)] and characterize it by spectroscopy. More information on the exact bonding and the anticipated reactivity of this highly strained compound are eagerly awaited.

  3. Editorial

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books
    1. You have free access to this content
      Enantioselective Reactions in a Static Magnetic Field-A False Alarm! (page 1457)

      Peter Gölitz

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414571

      Too good to be true—in hindsight unfortunately this must be said about a publication by G. Zadel et al. that appeared in the second February issue of Angewandte Chemie entitled “Enantioselective Reactions in a Static Magnetic Field”. The history of the publication and, in particular, the factors influencing the decision to publish are outlined. Regrettably, unnecessary time and effort were invested by many research groups worldwide in trying to reproduce these results. It is reassuring to know, however, that important publications are checked critically and very rapidly. In this particular case, established theories continue to hold true.

  4. Correspondences

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books
    1. Attempts to Carry Out Enantioselective Reactions in a Static Magnetic Field (pages 1458–1459)

      Prof. Dr. Ben L. Feringa, Prof. Dr. Richard M. Kellogg, Dr. Ron Hulst, Drs. Charon Zondervan and Wim H. Kruizinga

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414581

      They tried everything, but it still didn't work. Two research groups report here on their attempts to reproduce the results reported by Breitmaier et al. (Angew. Chem. Int. Ed. Engl.1994, 33, 454). According to the subsequent statement by E. Breitmaier (see p. 1414 this issue), the claim of absolute asymmetric synthesis in a static homogeneous magnetic field is fraudulent.

    2. Absolute Asymmetric Synthesis Solely under the Influence of a Static Homogeneous Magnetic Field? (pages 1459–1461)

      Prof. Dr. Gerd Kaupp and Thorsten Marquardt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414591

      They tried everything, but it still didn't work. Two research groups report here on their attempts to reproduce the results reported by Breitmaier et al. (Angew. Chem. Int. Ed. Engl.1994, 33, 454). According to the subsequent statement by E. Breitmaier (see p. 1414 this issue), the claim of absolute asymmetric synthesis in a static homogeneous magnetic field is fraudulent.

    3. Bond-Stretch Isomers and Spin-State Isomers: A Comment on the Article “Bond-Stretch Isomers: Fact not Fiction” (page 1462)

      Prof. Dr. Gerard Parkin and Prof. Roald Hoffmann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414621

      What exactly is meant by bond-stretch isomerism? Confusion seems to reign about the phenomenon, partly because the original papers did not explicitly define the term. However, if limited to its original meaning, no bond-stretch isomers have yet been discovered, in spite of a recent claim to the contrary (see Correspondence by P. Giitlich, H. A. Goodwin, and D. N. Hendrickson in the second February issue of Angewandte Chemie).

  5. Communications

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books
    1. Synthesis and Properties of a Vertically Stacked Porphyrin-Quinone(1)-Quinone(2) Cyclophane (pages 1463–1466)

      Prof. Dr. Heinz A. Staab, Dr. Moana Tercel, Dr. Rüdiger Fischer and Claus Krieger

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414631

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      Model compounds for the study of the primary processes in photosynthesis continue to spur chemists on to elaborate syntheses. Latest efforts have resulted in the triple-decker compounds (“triads”) 1 and 2, in which two quinone and one porphyrin, and one quinone and two porphyrin units, respectively, are linked in rigid arrangements.

    2. Synthesis and Properties of a Vertically Stacked Porphyrin(1)-Quinone(2)-Quinone Cyclophane (pages 1466–1468)

      Prof. Dr. Heinz A. Staab and Dr. Thomas Carell

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414661

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      Model compounds for the study of the primary processes in photosynthesis continue to spur chemists on to elaborate syntheses. Latest efforts have resulted in the triple-decker compounds (“triads”) 1 and 2, in which two quinone and one porphyrin, and one quinone and two porphyrin units, respectively, are linked in rigid arrangements.

    3. A Highly Convergent Synthesis of the Lewisy Blood Group Determinant in Conjugatable Form (pages 1468–1470)

      Victor Behar and Prof. Samuel J. Danishefsky

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414681

      The versatility of glycals both as glycosyl donors and as glycosyl acceptors is used in the synthesis of the Lewisy determinant. This and the oligosaccharide described in the following communication consist of a determinant, a carbohydrate spacer, and a group suitable for the conjugation to a carrier protein. The spacer present in these new glycoproteins minimizes the likelihood that the protein carrier will distort the recognition property of the determinant.

    4. An Interactive Strategy for the Assembly of Complex, Branched Oligosaccharide Domains on a Solid Support: A Concise Synthesis of the Lewisb Domain in Bioconjugatable Form (pages 1470–1473)

      John T. Randolph and Prof. Samuel J. Danishefsky

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414701

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      Minimal use of protecting groups is required in the synthesis of the branched hexa-saccharide Lewisb1. Thus, donor and acceptor glycosyl units were linked stereo-selectively to the polymer-bound glycal in such a way that an oligosaccharide recognition element is formed which can be bound to a carrier protein.

    5. The First Mononuclear Nitrosyl(oxo)molybdenum Complex: Side-On Bonded and μ3-Bridging NO Ligands in [{MoL(NO)(O)(OH)}2]NaPF6·H2O (pages 1473–1476)

      Jochen Böhmer, Gabriele Haselhorst, Prof. Dr. Karl Wieghardt and Dr. Bernhard Nuber

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414731

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      Linked through sodium ions to form a tetranuclear complex, the neutral unit [MoL(NO)(O)(OH)] of the title compound displays two types of bonding between the Na+ ions and NO (shown on the right) in the crystalline state. The bonding in this and similar monomeric nitrosyloxo complexes can be described by a synergistic bonding model. L = 1,4,7-triiso-propyl-1,4,7-triazacyclononane.

    6. On the Helicity of Oligomeric Formaldehyde (pages 1476–1478)

      Prof. Christian R. Noe, Dr. Christian Miculka and Dr. Jan W. Bats

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414761

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      Even this simple helical molecule, the benzyl-protected pentamer 1, has a few surprises in store. Two independent conformers of 1 with the same absolute configuration are found in the unit cell which demonstrate an unprecedented form of isomerism. The helicity of the oligomeric formaldehyde is definitely a consequence of stereoelectronic effects.

    7. Synthesis and Structure of the First [22]Metallocenophanes (pages 1479–1480)

      Prof. Dr. Klaus Hafner, Dr. Carsten Mink and Prof. Dr. Hans Jörg Lindner

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414791

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      The dark red Fe and colorless ZrCl2 complexes 2 are easily accessible from the doubly bridged biscyclopentadienes 1. The substantial torsion of the two eclipsing decks of the conformationally rigid ligand framework of 2 exposes the metal center and points to the potential of such complexes as catalysts for the stereoselective polymerization of alkenes.

    8. Heterodimetal–Betaine Chemistry: Catalytic and Stoichiometric Coupling of Alkynyl Ligands under the Joint Influence of Zirconium and Boron Centers (pages 1480–1482)

      Dipl.-Chem. Bodo Temme, Prof. Dr. Gerhard Erker, Dr. Roland Fröhlich and Dr. Matthias Grehl

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414801

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      Readily accessible from bis(propynyl)zirconocene, the organometallic betaines like 1 form by an intramolecular alkyne insertion and trapping reaction with tBuN[TRIPLE BOND]C from an intermediate that has a hexadiyne ligand unsymmetrically coordinated to the Zr and B centers. This diyne complex is obtained in a rapid C[BOND]C coupling reaction reaction between the starting material and B(C6F5)3.

    9. Chlorine Trioxide: Spectroscopic Properties, Molecular Structure, and Photochemical Behavior (pages 1482–1484)

      Dipl.-Chem. Hinrich Grothe and Prof. Dr. Helge Willner

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414821

      Though postulated for years, now detected for the first time! The symmetric ClO3 radical was synthesized by vacuum flash pyrolysis of chlorine perchlorate and trapped by matrix isolation for UV and IR spectroscopic studies. The O[BOND]Cl[BOND]O bond angle is 113.5±2° and the Cl[BOND]O bond length 150.0±1 pm. The photolysis of ClO3 yields the unsymmetric isomer OClOO.

    10. (tBuSi)2(PC6H11)3: A Propellane-Like Cyclosilaphosphane with Remarkable Structure (pages 1484–1487)

      Priv.-Doz. Dr. Matthias Driess, Prof. Dr. Rolf Gleiter, Prof. Dr. Rudolf Janoschek, Dr. Hans Pritzkow and Dipl.-Chem. Michael Reisgys

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414841

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      An unusually short Si[BOND]Si distance of 2.518(3) Å despite an antibonding interaction between these centers and a small endocyclic angle of 67° at phosphorus, these are the surprising structural features of the title compound 1, which forms by cyclocondensation of tBuSiFCl2 with CyPHLi in 33% yield. The structure of 1 reflects a tug-of-war between the three Si[BOND]P[BOND]Si and the six P[BOND]Si[BOND]P angles, Cy = cyclohexyl.

    11. A Highly Distorted and an Undistorted Borirane, C[BOND]B[BOND]H Hyperconjugation Induced by C[BOND]Si[BOND]H Hyperconjugation (pages 1487–1489)

      Dipl.-Chem. Christian Balzereit, Dipl.-Chem. Claudia Kybart, Dipl.-Chem. Heinz-Jürgen Winkler, Prof. Dr. Werner Massa and Prof. Dr. Armin Berndt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414871

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      Hyperconjugation is the reason for the different structures of 1 and 2: in 1 the electron deficiency of the boracyclohexadiene leads to strong hyperconjugation with the C[BOND]B bond in the spiro-linked three-membered ring, and between the thus more positive boron atom and a C[BOND]Si bond. In 2, in contrast, the electron deficiency of the boron atom of the four-membered ring is reduced by formation of a 2π electron homoarene by using the n electrons of the C[BOND]C double bond. Dur = 2,3,5,6-tetramethylphenyl, R = SiMe3.

    12. Stable Tetrakis(trialkylsilyl)disilenes; Synthesis, X-Ray Structures, and UV/VIS Spectra (pages 1489–1491)

      Prof. Dr. Mitsuo Kira, Dr. Toyotaro Maruyama, Dr. Chizuko Kabuto, Dr. Keisuke Ebata and Prof. Dr. Hideki Sakurai

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414891

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      Significant downfield shifts in the NMR spectrum are displayed by the central Si atoms in compounds 1 relative to those of disilenes not having four silyl substituents. The extraordinary color change of 1c on dissolving in hexane (yellow [RIGHTWARDS ARROW] deep red) is particularly impressive and indicates a conformational change caused by reduction in steric strain.

    13. The First Carbon–Phosphorus–Aluminum Cage Compounds: Cyclooligomerization of Phosphaalkynes with Trialkylaluminum Compounds (pages 1491–1493)

      Dr. Bernhard Breit, Dipl.-Chem. Andreas Hoffmann, Dr. Uwe Bergsträsser, Dr. Louis Ricard, Prof. Dr. François Mathey and Prof. Dr. Manfred Regitz

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414911

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      Depending on the solvent, two completely different products are obtained from the title reaction: the cage compound 1 (91%) is formed from 2 and AlEt3 (mol ratio 3:2) in n-hexane, whereas the polycycle 3 (74%) results from 2 and AlEt3 (mol ratio 4:1) in diethyl ether.

    14. Synthesis and Molecular Structure of Calcium Bis(trimethylstannanide)·4THF (pages 1493–1495)

      Dr. Matthias Westerhausen

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414931

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      A door to the underdeveloped organocalcium chemistry has possibly been opened with the synthesis of the title compound. Long Sn[BOND]C bonds and small C[BOND]Sn[BOND]C angles are found, which result from the predominantly ionic Ca[BOND]Sn bonding. The centrosymmetric Me3Sn[BOND]Ca[BOND]SnMe3 fragment has D36 symmetry.

    15. Keronopsins A and B, Chemical Defence Substances of the Marine Ciliate Pseudokeronopsis rubra (Protozoa): Identification by Ex Vivo HPLC (pages 1495–1497)

      Prof. Dr. Gerhard Höfle, Silke Pohlan, Dr. Gotram Uhlig, Karin Kabbe and Dorothee Schumacher

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414951

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      What happens when protozoa are injected onto an HPLC column? Because they do not have a rigid cell wall, they instantaneously release their contents, which can thus be analyzed without loss or opportunity for artefact formation (“ex vivo HPLC”). This method applied to the example, Pseudokeronopsis rubra (picture below), showed that the organism stores 1 in the form of the sulfate ester (R1 = SO3Na), which only on destruction of the cells is converted enzymatically into the more toxic pyrone 1 (R1 = H), R2 = H, Br.

    16. Single-Crystal EPR Spectroscopy on [57Fe(NO)(S2CNEt2)2]: The “Triplet Signal” in the EPR Spectrum of [Fe(S2CNEt2)3] (pages 1497–1499)

      Prof. Dr. Reinhard Kirmse, Dipl.-Chem. Simone Saluschke, Dipl.-Chem. Einar Möller, Dr. Eduard J. Reijerse, Dr. Edward Gelerinter and Prof. Dr. Norman V. Duffy

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414971

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      Traces of nitrate in the starting material FeCl3 lead to the formation of the analogous nitrosyliron(I) complex 2 during the synthesis of the tris(dithiocarbamato)iron complex 1. EPR studies on 57Fe-labeled 2 show that this complex gives rise to the triplet signal in the EPR spin-crossover studies on 1 at g = 2.0 that has been discussed for a long time.

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    17. Enol Triflate Pyranoses, Versatile Reagents for the Formation of Conjugated Systems on Pyranoses (pages 1499–1501)

      Dr. Yousef Al-Abed, Taleb H. Al-Tel, Christoph Schröder and Prof. Dr. Wolfgang Voelter

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199414991

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      In two steps and 85% yield the enol triflate pyranose 1 was prepared. This compound has proved to be well suited for the synthesis of pyranoses with conjugated elements.

    18. Luminescent Eu3+ and Tb3+ Complexes of a Branched Macrocyclic Ligand Incorporating 2,2′-Bipyridine in the Macrocycle and Phosphinate Esters in the Side Arms (pages 1501–1503)

      Prof. Dr. Nanda Sabbatini, Dipl.-Chem. Massimo Guardigli, Prof. Dr. Fabrizio Bolletta, Dipl.-Chem. Ilse Manet and Dr. Raymond Ziessel

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415011

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      Kinetic stability in water, good protection of the metal center, and strong luminescence of the metal ion make lanthanide complexes of the ligand 1 ([M⊂1]3+, M = Eu, Tb) promising as luminescent labels in fluoroimmuno-assays.

    19. A New Class of Novel Macrocyclic Mesogens (pages 1503–1506)

      Peter R. Ashton, Dr. Detlev Joachimi, Dr. Neil Spencer, Prof. J. Fraser Stoddart, Dr. Carsten Tschierske, Dr. Andrew J. P. White, Dr. David J. Williams and Kerstin Zab

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415031

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      The clearing temperature is unexpectedly higher for the liquid crystalline phases of the macrocycle 1 (209°C) than for comparable acyclic biphenyls. The coupling of two appropriate rigid units through flexible terminal chains is apparently a highly effective method of inducing and stabilizing the mesophase.

    20. 1,3-Dialkoxycalix[4]arenecrowns-6 in 1,3-Alternate Conformation: Cesium-Selective Ligands that Exploit Cation-Arene Interactions (pages 1506–1509)

      Prof. Dr. Rocco Ungaro, Dr. Alessandro Casnati, Dr. Franco Ugozzoli, Andrea Pochini, Dr. Jean-François Dozol, Clement Hill and Hélène Rouquette

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415061

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      Exceptionally high selectivity for cesium ions (α(Cs/Na) > 33000) is displayed by calix[4]arenecrowns-6 in the 1,3-alternate conformation. They also remove 137Cs quantitatively (>96%) from radioactive waste that is 1 M in HNO3. The complexation properties result from the simultaneous operation of several effects: the size of the crown ether ring, the polarity of the calix conformation, and the strength of the cation/π-electron interactions. The latter interaction was evident in the X-ray crystal structure of the cesium complex (shown on the right).

    21. Turcasarin, the Largest Expanded Porphyrin to Date (pages 1509–1512)

      Prof. Jonathan L. Sessler, Steven J. Weghorn, Vincent Lynch and Dr. Martin R. Johnson

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415091

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      40π-Electrons and ten pyrrole units are found in macrocycle 1, the largest expanded porphyrin reported thus far. The tetrahydrochloride salt of 1 was characterized in solution and in the solid state. These investigations indicate that the macrocycle exists as a pair of enantiomers whose chirality arises from a twist of the ring.

    22. Nonreactive Interactions between Ethene and Halogens: Detection of a π-Donor Complex C2H4BrCl by Rotational Spectroscopy (pages 1512–1513)

      Dr. Hannelore I. Bloemink, Kelvin Hinds, Prof. Anthony C. Legon and Joanna C. Thorn

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415121

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      The outer complex initially formed on electrophilic addition has been shown to have the structure 1 in the prototypical reaction of ethene with BrCl. The rotational spectra of two isotopomers of a weakly bound complex were observed by Fourier transform microwave spectroscopy with a fast-mixing nozzle. This result is important for the understanding of the mechanism of electrophilic addition, a fundamental reaction in organic chemistry.

    23. Stable Flexible Fibers and Rigid Tubules Made from Single-Chain Perfluoroalkylated Amphiphiles (pages 1514–1515)

      Françoise Giulieri, Dr. Marie-Pierre Krafft and Prof. Jean G. Riess

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415141

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      Up to 50 um long, stable, cylindrical aggregates (shown on the right) are formed spontaneously from dispersions of perfluoroalkylated, single-chain, nonchiral amphiphiles derived from dimorpho-linophosphoramidate and phosphocholine. Depending on the polar head group, rigid hollow tubules or thinner, longer, flexible fibers are obtained. Thus, the strong hydrophobic effect of the fluorinated chains alone appears to be sufficient to promote the formation of assemblies more stable than vesicles.

    24. Metal Complexes of Marine Peptide Metabolites: A Novel Ag4 Cluster (pages 1516–1518)

      Prof. Dr. Peter Wipf, Srikanth Venkatraman, Chris P. Miller and Dr. Steven J. Geib

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415161

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      Silver(I) ions are bound selectively and with high cooperativity to the peptide westiellamide obtained from Lisso-clinum. The complex contains a unique [Ag4]4+ cluster sandwiched between two neutral macrocyclic ligands (see structure on the right). The importance of metal chelation for the biological activity is currently under investigation.

    25. Synthesis and Structure of the First Titanium(IV) α-Amino Acid Complexes (pages 1518–1519)

      Priv.-Doz. Dr. Thomas M. Klapötke, Prof. Dr. Hartmut Köpf, Dr. Inis C. Tornieporth-Oetting and Dr. Peter S. White

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199415181

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      Cytostatically active titanocene dichloride reacts with α-amino acids to give titanium(IV) amino acid complexes of the type [Cp2Ti(aa)2]2+ [Cl]2 (aa = α-amino acid). The structure of the cation (1) in the corresponding 2-methylalanine complex is shown on the right.

  6. Book Reviews

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books
  7. New Books

    1. Top of page
    2. Reviews
    3. Highlights
    4. Editorial
    5. Correspondences
    6. Communications
    7. Book Reviews
    8. New Books

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