Angewandte Chemie International Edition in English

Cover image for Vol. 26 Issue 8

August 1987

Volume 26, Issue 8

Pages 707–804

Currently known as: Angewandte Chemie International Edition

    1. Cover Picture (Angew. Chem. Int. Ed. Engl. 8/1987)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707071

      Thumbnail image of graphical abstract

      The cover shows the calculated structure of the 1,3-dehydro-5,7-adamantane-diyl dication [C4(CH2)6]2⊕, which, owing to three-dimensional homoaromaticity, is exceptionally stable. The compound demonstrates once again the value of calculations: not only was the stability of the compound predicted, but even the 13C chemical shifts could be calculated in advance with surprising accuracy. The dication contains a four-center two-electron bond (dashed red line) in the interior, the C atoms exhibiting significant overlap (0.38 versus about 0.7 for a normal C[BOND]C bond). The positive charge is not only localized on the bridgehead C atoms, but also on the H atoms of the CH2 groups. Further details are reported by P. von R. Schleyer et al. on page 761ff.

  1. Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    1. The Nerve Growth Factor: 35 Years Later (Nobel Lecture) (pages 707–716)

      Prof. Dr. Rita Levi-Montalcini

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707073

      Growth factors—for nerves and for epidermal tissue—are the areas of research of last year's recipients of the Nobel Prizes for Medicine. The growth of nerves and of epidermal tissue requires a chemical stimulant. Nerve growth factor (NGF) proved to be a freely diffusing protein that is essential for the normal development of embryos, but which, in excess, results in major disruption of neurogenic processes. NGF has been isolated from several sources, including the salivary glands of mice. Crude extracts of NGF had unexpected side effects, the systematic investigation of which led to the discovery of epidermal growth factor (EGF). EGF, like NGF, is a protein, whose sequence has been determined. The primary signal mediated by EGF is thought, at present, to involve the tyrosine kinase activity of its receptor.

    2. Epidermal Growth Factor (Nobel Lecture) (pages 717–722)

      Stanley Cohen

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707171

      Growth factors—for nerves and for epidermal tissue—are the areas of research of last year's recipients of the Nobel Prizes for Medicine. The growth of nerves and of epidermal tissue requires a chemical stimulant. Nerve growth factor (NGF) proved to be a freely diffusing protein that is essential for the normal development of embryos, but which, in excess, results in major disruption of neurogenic processes. NGF has been isolated from several sources, including the salivary glands of mice. Crude extracts of NGF had unexpected side effects, the systematic investigation of which led to the discovery of epidermal growth factor (EGF). EGF, like NGF, is a protein, whose sequence has been determined. The primary signal mediated by EGF is thought, at present, to involve the tyrosine kinase activity of its receptor.

    3. Diene, Alkyne, Alkene, and Alkyl Complexes of Early Transition Metals: Structures and Synthetic Applications in Organic and Polymer Chemistry (pages 723–742)

      Prof. Dr. Hajime Yasuda and Prof. Dr. Akira Nakamura

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707231

      Thumbnail image of graphical abstract

      The unique structure and reactivity of diene complexes of Ti, Zr, Hf, Nb, and Ta is a fascinating area of organometallic chemistry. One example is provided by the isoprenezirconium complex 1, which is characterized by a novel, bent metallacyclo-3-pen-tene structure. Complex 1 undergoes nucleophilic addition to carbonyl compounds and nitriles with unusually high regioselectivity.

    4. RP-Bridged Metal Carbonyl Clusters: Synthesis, Properties, and Reactions (pages 743–760)

      Prof. Dr. Gottfried Huttner and Dipl.-Chem. Konrad Knoll

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707431

      Thumbnail image of graphical abstract

      The reactivity of clusters has been investigated in only a few cases, whereas a multitude of syntheses have been reported. The systematic study of reaction pathways is made possible by the incorporation of RP bridges into clusters. They hold the metal carbonyl fragments together even when metal-metal bonds are broken (see 1 [RIGHTWARDS ARROW] 2).

  2. Communications

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    1. Four-Center Two-Electron Bonding in a Tetrahedral Topology. Experimental Realization of Three-Dimensional Homoaromaticity in the 1,3-Dehydro-5,7-adamantanediyl Dication (pages 761–763)

      Dipl.-Chem. Matthias Bremer, Prof. Dr. Paul von Ragué Schleyer, Dr. Karl Schötz, Dr. Michael Kausch and Dr. Michael Schindler

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707611

      Thumbnail image of graphical abstract

      A nonclassical structure for the dication 3 is supported, in particular, by the 13C-NMR data: the signals of the bridgehead C atoms are shifted upfield (δ = 6.6) and not downfield, as would have been expected for a classical dication. The resonances of the methylene C atoms are observed at δ = 35.6 (1H-NMR: δ = 3.8). Compound 3 is synthesized starting from 1,3,5,7-tetra-iodoadamantane, which reacts with HgF2 to give 1. Compound 1 reacts with nBuLi to give 2, from which 3 can be generated. The dication 3 is stable up to 0°C.

    2. Dimenzation of 1,6-Ditiniacycioaeca-3,8-diyne in the Presence of Cobalt Complexes. A Simple Synthesis of a [2.2](2,5)Thiophenophane Derivative (pages 763–764)

      Prof. Dr. Rolf Gleiter, Dipl.-Chem. Michael Karcher, Dr. Bernhard Nuber and Prof. Dr. Manfred L. Ziegler

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707631

      Thumbnail image of graphical abstract

      The CH2/S analogy in the reaction of the ten-membered rings 1 and 2 with CpCo complexes is limited to the formation of phanes. Whereas 1 affords a cyclobutadieno-super-phane containing two coordinated CpCo fragments, 2 yields the cobalt-free dimer 3 in a single step.

    3. Bis(η5-cyclopentadienyl)-1,3-diphosphabicyclo[1.1.0]butane-2,4-diylzirconium: A Simple Synthesis of an Unusual Molecule (pages 764–765)

      Priv.-Doz. Dr. Paul Binger, Dipl.-Chem. Bruno Biedenbach, Prof. Dr. Carl Krüger and Prof. Dr. Manfred Regitz

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707641

      Thumbnail image of graphical abstract

      The metal-substituted diphosphabicyclobutane 1 and not the expected metalladiphosphacyclopentadiene was formed in the reaction shown below. The distances show unequivocally that a P[BOND]P bond but no Zr[BOND]P bond is present in 1. The tBu groups are arranged in a nearly eclipsed fashion.

    4. The Role of Debye Screening Length in Ordered Arrays of Cylindrical Nickel Dimethylglyoxime Particles (pages 765–767)

      Prof. Dr. Tsuneo Okubo

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707651

      The electrostatic repulsion between colloid particles and the important role of Debye screening length are exemplified by particles of nickel dimethylglyoxime. In sedimentation equilibrium in salt-free solution, the cylindrical particles form hexagonal arrays like those formed by tobacco mosaic virus. These arrays can be observed under a microscope. The Young's modulus of the lattice structures is 0.47 Pa.

    5. Metathesis of CS2-Like Heteroallenes on 1,1-Dithio Complexes of Rhodium(III) (pages 767–768)

      Dr. Claudio Bianchini, Dr. Andrea Meli and Dr. Franco Vizza

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707671

      Thumbnail image of graphical abstract

      A [2 + 2] cycloaddition via the intermediate A provides an explanation for the metathesis reactions of S[DOUBLE BOND]C[DOUBLE BOND]S, S[DOUBLE BOND]C[DOUBLE BOND]NPh, and S[DOUBLE BOND]C[DOUBLE BOND]NEt. These reactions proceed under very mild conditions. In the formulas shown below, the triphos ligands and the anions have been omitted.

    6. Reactions of [Pd2(μ-dppm)2Cl2] with Electrophilic Complexes of Copper and Gold. Synthesis of the Pd4 Cluster [Pd4(μ-Cl)2(μ-dppm)4](PF6)2·2(CH3)2CO (pages 768–770)

      Dr. Pierre Braunstein, Dr. Michael A. Luke, Prof. Antonio Tiripicchio and Prof. Marisa Tiripicchio Camellini

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707681

      Thumbnail image of graphical abstract

      The structure of the dication 1 of the title compound is both surprising and unique. Complex 1 is formed from [Pd2(μ-dppm)2Cl2] and the product obtained by reaction of [(Ph3P)CuBr]4 and TIPF6. The same dipalladium complex also reacts with [Cu(CH3CN)4]BF4 to give quantitatively 1 (BF4)2. The analogous diplatinum compound, on the other hand, affords A-frame complexes (dppm = Ph2P[BOND]CH2[BOND]PPh2).

    7. The Effect of Solvent on the Stability of mero-Substituted Alkyl Radicals (pages 770–771)

      Dr. Hans-Dieter Beckhaus and Prof. Dr. Christoph Rüchardt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707701

      Thumbnail image of graphical abstract

      The “captodative effect”—does it indeed exist? Neither the reaction enthalpy nor the activation enthalpy for the dissociation of 2 (R [DOUBLE BOND] C6H5; t-C4H9) decreases in polar solvents (ethylene glycol, succinic anhydride, N-methylacetamide) in comparison to the values measured in diphenyl ether or mesitylene. This finding contradicts the recently suggested strong stabilization of mero- or captodative-substituted alkyl radicals, such as 1, by polar solvents.

    8. A 1-Oxa-2-nickela-5-cyclopentanone from Ethene and Carbon Dioxide: Preparation, Structure, and Reactivity (pages 771–773)

      Prof. Dr. Heinz Hoberg, Dr. Yolande Peres, Prof. Dr. Carl Krüger and Dr. Yi-Hung Tsay

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707711

      Complex 1 is a key intermediate in the Ni0-promoted C[BOND]C bond formation between alkenes and CO2; it contains 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as ligand. The Ni[BOND]C bond of 1 can participate in further, regioselective insertion reactions with alkenes. The nickelacycle is thus a model complex for the study of Ni-catalyzed reactions.

      • equation image
    9. Inversion of the Configuration of Secondary Alcohols via Isourea Ethers Prepared in situ (pages 773–774)

      Dr. Johannes Kaulen

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707731

      Thumbnail image of graphical abstract

      The “inverting esterification” of the secondary alcohols 1 via the title compounds 2 is accomplished in a one-pot procedure. The enantiomers 4 are obtained following alkaline hydrolysis. R3 is usually H. The inversion proceeds with > 99% ee (or de); the procedure is less expensive to carry out and the work-up is easier to perform compared with the Mitsunobu procedure.

    10. Structure Elucidation of a New Icosapeptide from Human Semen (pages 774–776)

      Dr. Klaus Schneider, Josef Reiner and Prof. Dr. Gerhard Spiteller

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707741

      Only 300 μg of the new oligopeptide 1 was available for a structure determination. The sequence could be determined by a combination of liquid secondary ion mass spectrometry (LSIMS) and Edman degradation. Crucial for this success was the observation that the sample used for the mass spectrometric analysis could be eluted unchanged from the target and subsequently used for an Edman degradation.

      • equation image
    11. Phosphasilirenes, Three-Membered Rings Containing PC Double Bonds (pages 776–777)

      Dr. Annemarie Schäfer, Prof. Dr. Manfred Weidenbruch, Dipl.-Chem. Wolfgang Saak and Prof. Dr. Siegfried Pohl

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707761

      Thumbnail image of graphical abstract

      The similarity of phosphaalkynes and acetylenes is revealed in the [2 + 1] addition of di(tert-butyl)silanediyl. Reaction of RC[TRIPLE BOND]P and tBu2Si: results in the formation of the isolable title compounds 1 (a, R [DOUBLE BOND] tBu; b, adamantyl), the first three-membered ring compounds containing a P[DOUBLE BOND]C bond. A W(CO)5 adduct of 1b proved to be sufficiently stable for an X-ray structure analysis.

    12. Synthesis and Chirality of Sixfold-Bridged Triple-Decker Phanes (pages 777–779)

      Dipl.-Chem. Norbert Sendhoff, Dipl.-Chem. Karl-Heinz Weissbarth and Prof. Dr. Fritz Vögtle

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707771

      Thumbnail image of graphical abstract

      The name “superphane” has already been used—it would have been appropriate for the title compound! The first triple-decker phane containing six bridges was synthesized (in a single cyclization step) starting from the three layers. Two isomeric triple-decker phanes were isolated. One of these is helically chiral; it could be separated chromatographically to give the stable enantiomers—1 and its mirror image.

    13. 1,4-Diphospha-1,3-butadienes (pages 779–780)

      Prof. Dr. Rolf Appel, Johannes Hünerbein and Nikolaos Siabalis

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707791

      The similar behavior of PC and CC double bonds is revealed, in particular, in compounds containing both types of π bond, for example in phospha-1,3-butadienes. Up to three C atoms have been so far replaced by P atoms in various positions of butadiene. It has now been possible—thanks to the use of bulky substituents—to synthesize, for the first time, two 1,4-diphospha-1,3-butadiene derivatives.

    14. Synthesis and Structure of a Stable Iodoselenide (pages 780–781)

      Prof. Dr. Wolf-Walther du Mont, Dipl.-Chem. Silvia Kubiniok, Dr. Karl Peters and Prof. Dr. Hans-Georg von Schnering

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707801

      Thumbnail image of graphical abstract

      Although the diselane 1 is stable upon exposure to air, it is attacked rapidly by iodine, resulting in the formation of 2,4,6-tri-tert-butylphenyl(iodo)selenide 2. Compound 2, which forms anthracite-black crystals melting at 156°C, is also monomeric in the solid state, the Se[BOND]I bond being 252.9 pm long. Upon dissolving, 2 decomposes to the starting materials.

    15. Synthesis and Structure of a 2,5-Dihydro-1H-1,2,5-phosphadiborole Derivative (pages 781–782)

      Matthias Driess, Dr. Hans Pritzkow and Prof. Dr. Walter Siebert

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707811

      Thumbnail image of graphical abstract

      A puckered five-membered ring exhibiting pyramidal coordination at the P atom characterizes the title compounds 2 (R = Me, Et, iPr). The new C2B2P heterocycles can be obtained in good yields from the corresponding ethene derivatives 1 and C6H5PLi2.

    16. Concerning the Structure of Benzene (pages 782–784)

      Prof. Dr. Otto Ermer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707821

      The D6h structure of benzene has not yet been proven—that is the quintessence of an informative discussion in which all available experimental (and theoretical) findings were examined in order to determine whether or not they definitively rule out the “Kekule structure” (D3h.)-Neither spectroscopic nor diffraction methods of analysis provide data that are in disagreement with the D3h, structure. The discussion of the structure of benzene in textbooks should therefore be formulated more carefully. Furthermore, one should exercise caution in analyzing the alternation of CC bond lengths in annulenes by X-ray diffraction.

    17. The Absolute Configuration of the Ant Alarm Pheromone Manicone (pages 784–785)

      Prof. Dr. Hans Jürgen Bestmann, Dr. Athula B. Attygalle, Dipl.-Chem. Jürgen Glasbrenner, Dipl.-Chem. Roland Riemer and Dr. Otto Vostrowsky

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707841

      Thumbnail image of graphical abstract

      Only roughly ten ants were necessary to determine the absolute configuration of the long known alarm pheromone manicone, 1. Naturally occurring and rac-1 were hydrogenated and compared to the optically active, synthetic compound by complexation chromatography. Compound 1 was shown to have the 6S configuration.

    18. Reduction of 2-Enoates and Alkanoates with Carbon Monoxide or Formate, Viologens, and Clostridium thermoaceticum to Saturated Acids and Unsaturated and Saturated Alcohols (pages 785–787)

      Prof. Dr. Helmut Simon, Dr. Hiltrud White, Dr. Herbert Lebertz and Dr. Iordanes Thanos

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707851

      Thumbnail image of graphical abstract

      The biochemical system used to carry out the title reactions in aqueous solution is probably also of preparative value. The unsaturated carboxylates 1 afford the saturated analogues 2 at pH 7.5 in the presence of CO, H2, or HCOO and give the alcohols 3 and 4 at pH 5.5; with the same reagents at pH 5.5, the transformation 2[RIGHTWARDS ARROW]3 occurs. The carboxyl groups of compounds 1 and 2 are not activated in this process as is the case in the corresponding biological reactions. R1, R2 = Me, Ph, CH[DOUBLE BOND]CHCH3.

    19. [(η5-C5Me5)Re(CH3)4], the First Organorhenium(V) Compound without Heteroatom Ligands (pages 787–789)

      Martina Flöel, Dr. Eberhardt Herdtweck, Werner Wagner, Jürgen Kulpe, Dr. Peter Härter and Prof. Dr. Wolfgang A. Herrmann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707871

      Thumbnail image of graphical abstract

      Extreme light, air, and moisture sensitivity characterize the title compounds 1, h which form brilliant red crystalline platelets that are stable for long periods of time at dry-ice temperature. They were obtained by reaction of CH3MgCl with (C5Me5)ReCl4 in a molar ratio of 4:1 (yields 40–50%). The paramagnetic complex 1 has a tetragonalpyramidal molecular structure.

    20. Pentabenzylcyclopentadienylthallium(I): Synthesis and Structure of a “Dimeric” Organothallium Compound with Tl[BOND]Tl Interaction (pages 789–790)

      Prof. Dr. Herbert Schumann, Dr. Christoph Janiak, Prof. Dr. Joachim Pickardt and Ute Börner

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707891

      A protective shield consisting of six benzyl groups envelops a Tl1[BOND]Tl1 unit in the title compound. The Tl–Tl distance of 3.6 Å does not correspond to that of a normal single bond but does indicate a bonding interaction—perhaps similar to that in Cu1[BOND]Cu1 and Au1[BOND]Au1 complexes. Normally, cyclopentadienylthallium complexes do not have a dimeric structure but rather a polymeric structure containing zigzag chains.

    21. Substituted α-Pyrones as Starting Compounds for the Synthesis of 4,4-Disubstituted 1,4-Dihydropyridines (pages 790–791)

      Dr. Vratislav Kvita and Hans-Peter Sauter

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707901

      Thumbnail image of graphical abstract

      The synthesis of the title compound 1 may provide a way of obtaining new calcium antagonists. Compound 1, R[DOUBLE BOND]NO2 combines, for the first time, all the structural features that have proven to be especially advantageous.

    22. The Spin Distribution in Ion Pairs of 1-Aminoanthraquinone Radical Anion and Alkali-Metal Cations (pages 791–793)

      Prof. Dr. Hans Bock, Dipl.-Chem. Bernhard Hierholzer and Dipl.-Chem. Petra Schmalz

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707911

      Thumbnail image of graphical abstract

      The ENDOR spectra of the contact-ion-pair radicals 1, M [DOUBLE BOND] Li or Cs, which were generated by stoichiometric alkali-metal reduction of 1-aminoanthraquinone and further stabilized by tetrahydrofuran (THF), differ in significant ways and afford detailed insight into the structure of this species. As the effective ionic charge of M increases, the spin density on the complexing O atoms decreases and the π spin density at the ring C atoms and the corresponding H couplings increase.

    23. Lactosylceramides with Unsaturated Fatty Acids—Synthesis and Use in the Generation of Bilayer Membranes (pages 793–794)

      Prof. Dr. Richard R. Schmidt, Dipl.-Chem. Thomas Bär and Dr. Hans-Juergen Apell

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707931

      Thumbnail image of graphical abstract

      The lactosylceramides 1–4 form bilayer membranes having longevities of several hours as well as electrical capacities that are appreciably larger than those of phosphatidylcholine membranes. Important for the preparation of the planar bilayers is the use of chemically pure glycosphingolipids. Compounds 1–4 were synthesized in only a few steps in good yields.

    24. Deep-Colored, Through-Conjugated Multitriphenylmethylium Ions (pages 794–796)

      Prof. Dr. Dieter Hellwinkel, Dipl.-Chem. Heinz Stahl and Dipl.-Chem. Heinrich Georg Gaa

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707941

      Thumbnail image of graphical abstract

      The first members 1 and 2 of a series of novel multitritylium ions were obtained by treatment of the trityl ether precursors with very strong acids. The tritylium ions known so far have been yellow to orange, whereas the new compounds are intense red and red-violet, respectively. In the 1H-NMR spectrum, the para protons of the terminal phenyl groups exhibit record screening values of δ = 8.84 and 8.68, respectively.

    25. A Psoralen-Substituted Dioxetane as DNA Intercalator for Photogenotoxic Studies (pages 796–797)

      Prof. Dr. Waldemar Adam, Dipl.-Chem. Axel Beinhauer, Roland Fischer and Dr. Hermann Hauer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707961

      Thumbnail image of graphical abstract

      The dioxetane derivative 1 of psoralen is a very promising compound. As a polycyclic heteroarene, 1 presumably undergoes intercalation into DNA; subsequent thermal decomposition of the dioxane moiety should lead to the formation of excited psoralen, which should, in turn, undergo cycloaddition to DNA. The effect of psoralen in treating psoriasis is based on such a cycloaddition.

    26. Cerium (IV)-Catalyzed Single Electron Transfer (SET) on Acenaphthene and 1,4-Dihydronaphtho-[1,8-d,e][1,2]diazepine: Chemical Evidence for Distinct Radical Cations (pages 797–798)

      Prof. Dr. Waldemar Adam, Alicia Casado and Prof. Dr. Miguel A. Miranda

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707971

      Thumbnail image of graphical abstract

      The differing chemical behavior of the title compounds 1 and 2 in the SET reaction shows that different radical cations are formed from 1 and 2. The valence isomerization of 1⊙⊕ and 2⊙⊕ is slow on the chemical time scale. This is probably due to the fact that a C[BOND]C bond must be broken for the transformation 1⊙⊕[RIGHTWARDS ARROW] 2⊙⊕; a high activation energy is presumably also required for the transformation 2 [RIGHTWARDS ARROW] 1.

    27. Stable Germaethenes (pages 798–799)

      Harald Meyer, Gerhard Baum, Priv.-Doz. Dr. Werner Massa and Prof. Dr. Armin Berndt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707981

      Thumbnail image of graphical abstract

      Lemon-yellow crystals, which melt at 167°C without decomposition, are formed by the first kinetically stabilized germaethene 3, prepared from 1 and 2. The C[DOUBLE BOND]Ge bond of 3 is considerably less twisted than the analogous C[DOUBLE BOND]Sn bond in a stannaethene and it is only slightly longer (1.827(4) Å) than that calculated for H2Ge[DOUBLE BOND]CH2 (R[DOUBLE BOND]N(SiMe3)2).

    28. Preparation of F4S[DOUBLE BOND]CH[BOND]COF by Isomerization of F5S[BOND]CH[DOUBLE BOND]C[DOUBLE BOND]O (pages 799–801)

      Dipl.-Chem. Thomas Krügerke, Dr. Jürgen Buschmann, Prof. Dr. Gert Kleemann, Prof. Dr. Peter Luger and Prof. Dr. Konrad Seppelt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198707991

      The alkylidene sulfur tetrafluoride 3 containing a functional group may be prepared simply and in good yield in two steps starting from 1. The ketene 2 is also new. The driving force for the isomerization 2 [RIGHTWARDS ARROW] 3 is the transformation of cumulative double bonds to conjugated double bonds. An X-ray structure analysis of 3 at −168°C revealed that the double bond system is cisoid-planar.

      • equation image
  3. Book Reviews

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

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    5. Corrigenda
    1. You have free access to this content
      Corrigendum (page 804)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.198708041

SEARCH

SEARCH BY CITATION