Angewandte Chemie International Edition in English

Cover image for Vol. 33 Issue 12

June 6, 1994

Volume 33, Issue 12

Pages 1201–1306

Currently known as: Angewandte Chemie International Edition

    1. Cover Picture (Angew. Chem. Int. Ed. Engl. 12/1994)

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199411991

      Thumbnail image of graphical abstract

      The cover picture shows the spliceosome cycle, in which CC, A, b1, B2, C1, C2, and 1 represent splice complexes within the splicing pathway that have been distinguished biochemically and/or genetically and which are formed from precursor RNA (pre-RNA) and small nuclear ribonucleoproteins (shown in color). Pre-RNA enters these complexes and exits as mRNA and excised lariat RNA (left). RNA splicing of split genes contributes to the great variety of proteins. During this splicing process, which occurs in eukaryotic cells, “superfluous” RNA sequences (introns) are spliced from the pre-RNAs, and the remaining RNA segments, the exons, are joined. In this way, depending on the combination of exons, different mRNAs—and from these subsequently proteins with different functions—are generated, which, for example, is clearly cirtical for the viability of many vertebrate organisms, Phillip A. Sharp in his Nobel lecture on p. 1229 ff. reports on the discovery of RNA splicing and on the splicing mechanisms.

  1. Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    1. The Polymerase Chain Reaction (Nobel Lecture) (pages 1209–1213)

      Dr. Kary B. Mullis

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412091

      What did it feel like to invent the polymerase chain reaction? In his Nobel Lecture K. B. Mullis gives an entertaining and philosophical account of his journey that resulted in a powerful new method, completely automated in the meantime, for the synthesis of as much identical DNA as desired from one single strand.

    2. Synthetic DNA and Biology (Nobel Lecture) (pages 1214–1221)

      Prof. Michael Smith

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412141

      Double helices of short oligonucleotides formed the starting point for the studies of M. Smith for the application of synthetic oligonucleotides in biochemistry. This led to processes for isolation of genes and sequencing double-stranded DNA and to the determination of mRNA ends, mutagenesis, and genotype selection.

    3. An Amazing Distortion in DNA Induced by a Methyltransferase (Nobel Lecture) (pages 1222–1228)

      Prof. Dr. Richard J. Roberts

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412221

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      Not a bend or kink in the DNA, but the flip of the base to be methylated out the DNA helix (picture on the right) occurs when a methyltransferase binds to DNA. This was the key result of the X-ray structure analysis of a ternary complex of M. HhaI, AdoMet, and a 5-fluorocytosine-substituted DNA double helix. This conformational shift may generally play a major role in the opening up of DNA helices.

    4. Split Genes and RNA Splicing (Nobel Lecture) (pages 1229–1240)

      Prof. Phillip A. Sharp

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412291

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      The discovery in 1977 that genes of eukaryotic organisms contain nonsense segments (“introns”) earned P. A. Sharp the 1993 Nobel Prize for Medicine. The introns at the stage of RNA are displaced by spliceosomes or in a self-splicing process (outlined schematically below). A denotes an adenosine residue, P phosphate groups, the rectangles RNA sequences that are joined together, and the lines the intron that is spliced.

  2. Communications

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    1. Recombinant Whole Cells as Catalysts for the Enzymatic Synthesis of Oligosaccharides and Glycopeptides (pages 1241–1242)

      Guido F. Herrmann, Peng Wang, Gwo-Jenn Shen and Chi-Huey Wong

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412411

      An easier, faster, cheaper approach to the enzymatic synthesis of oligosaccharides would be to employ whole cells rather than purified enzymes. In this report recombinant E. coli cells mediate the mannosylation of monosaccharides and glycopeptides. It was also proven that the relevant enzyme, mannosyl transferase, does not leak from the periplasmic space of the cells into the medium.

    2. Remarkable Stereoselectivity in the Inhibition of α-Galactosidase from Coffee Bean by a New Polyhydroxypyrrolidine Inhibitor (pages 1242–1244)

      Dr. Yi-Fong Wang, Dr. Yoshikazu Takaoka and Prof. Dr. Chi-Huey Wong

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412421

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      A potent inhibitor is easily accessible. The pyrrolidine derivative 1 effectively inhibits α-galactosidase (Ki = 5 × 10−8 M), since it mimics the transition state structure of the cleavage of the glycosidic bond. Compound 1 can be prepared by chemical (see below) and chemoenzymatic routes.

    3. Synthesis and Structure of the First Organometallic Galloxane Hydroxide Mes6Ga6O4(OH)4 (pages 1244–1246)

      Dipl.-Chem. Jens Storre, Dipl.-Chem. Thomas Belgardt, Priv.-Doz. Dr. Dietmar Stalke and Prof. Dr. Herbert W. Roesky

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412441

      Thumbnail image of graphical abstract

      Controlled hydrolysis of (mesityl)2GaOH leads to the first structurally characterized galloxane hydroxide 1, which crystallizes as [l(thf)4]-6THF. The framework of 1 consists of a distorted Ga6 octahedron whose faces are capped alternately by μ3-O or μ3-OH ligands. Only the ipso-C and O atoms of the mesityl and four THF substituents, respectively, are shown in the picture on the right.

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    4. Benziporphyrin, a Benzene-Containing, Nonaromatic Porphyrin Analogue (pages 1246–1247)

      Dipl.-Chem. Kurt Berlin and Prof. Dr. Eberhard Breitmaier

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412461

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      Benzene wins the battle for aromaticity against [18]annulene. The first fully conjugated, benzene-containing porphyrin analogue 1 is not an 18 π aromatic system; only the tautomer with the intact arene is observed. This compound is synthesized from the corresponding tripyrranedicarboxylic acid and isophthalaldehyde and forms black-blue crystals.

    5. Synthesis and Reactivity of a Naphtho[l,8-bc]boret (pages 1247–1248)

      Dr. Achim Hergel, Dr. Hans Pritzkow and Prof. Dr. Walter Siebert

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412471

      Thumbnail image of graphical abstract

      peri-Bridging of naphthalene by a boron atom causes a large distortion in the sp2 bond angles at C1 and C8 in the naphtho[l,8-bc]boret 1. The resulting ring strain is evident in the chemistry of 1: on treatment with electron-poor boron compounds BX3 an unexpected ring expansion to 2 (X = Cl, Br, OEt) is observed.

    6. C2H2Si Isomers: Generation by Pulsed Flash Pyrolysis and Matrix-Spectroscopic Identification (pages 1248–1250)

      Prof. Dr. Günther Maier, Dr. Hans Peter Reisenauer and Dipl.-Chem. Harald Pacl

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412481

      Thumbnail image of graphical abstract

      To what extent can ab initio calculations be trusted? Is silacyclopropyne (1) a transition state or an energy minimum? The experimental work described here demonstrates that all four C2H2Si isomers 1–4 can exist.

    7. Synthesis of Centrohexacyclic Hydrocarbons by the Propellane Route: Centrohexaindan and Tribenzocentrohexaquinane (pages 1251–1253)

      Dr. Dietmar Kuck, Dr. Bernd Paisdor and Dipl.-Chem. Detlef Gestmann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412511

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      Topologically nonplanar hydrocarbons 2 and 3 are available from triptindantrione 1 in only a few steps. Threefold addition of PhLi to 1 and subsequent cyclodehydration provides 2. In contrast, threefold addition of LiC[TRIPLE BOND]CR leads surprisingly to a centrohexacyclic tris(enol ether), which can be isomerized thermally into the corresponding triketone.

    8. Base-Free Monomeric Organogallium Hydrides (pages 1253–1255)

      Prof. Alan H. Cowley, François P. Gabbaï, Harold S. Isom, Prof. Carl J. Carrano and Dr. Marcus R. Bond

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412531

      Thumbnail image of graphical abstract

      Stable tricoordinate mono- and dihydrides of gallium, 1 and [(Ar)Ga(H)2], respectively, can be isolated by taking advantage of the kinetic stabilization afforded by bulky Ar substituents. The monohydride 1, prepared from [(Ar)2GaCl] and Li-GaH4, is the product of an unusual rearrangement reaction. Ar = 2,4,6-tBuC6H2.

    9. The Bonding Capability of Imido Complex Fragments of Groups 5–7 with Regard to the Isolobal Relationship (pages 1255–1257)

      Dr. Jörg Sundermeyer and Dipl.-Chem. Diane Runge

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412551

      Thumbnail image of graphical abstract

      The same number of valence orbitals and valence electrons, as well as valence orbitals of similar symmetry and energy, results when the cyclopentadienyl ligand in [(η5-C5R′5)M] is substituted by an imido ligand NR and the metal atom by an isoelectronic M′ of the next higher group (see the series below). Through coupling of the imido complex fragments with [CpFe(CO)2], the characteristic bonding capability of each entity can be determined.

    10. A Novel Organomagnesium Compound Consisting of Two Triple-Decker Cations [LMg(μ-Me(3)MgL]+ and an Octamethyltrimagnesate Anion: [{Me2Mg(μ-Me)2}2Mg]2− (pages 1257–1259)

      Dr. Heiko Viebrock, Prof. Dr. Ulrich Behrens and Prof. Dr. Erwin Weiss

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412571

      Thumbnail image of graphical abstract

      The disproportionation of dimethylmagnesium to give novel organomagnesium ions is possible with the tripod ligand N,N′,N″-trimethyl-l,4,7-triazacyclononane (tacn). The cation in 1 has a triple-decker structure (shown on the right); the anion is the first trimagnesate, whose structure is intermediate to those of monomeric and polymeric compounds.

      • equation image
    11. A Kinetic Study of the Hydrolysis of Phosgene in Aqueous Solution by Pulse Radiolysis (pages 1259–1261)

      Dipl.-Chem. Ralf Mertens, Prof. Dr. Clemens von Sonntag, Dr. Johan Lind and Dr. Gabor Merenyi

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412591

      Since the free radical induced degradation of chlorinated hydrocarbons yields phosgene, the exact kinetic data for phosgene′s behavior in aqueous solution is of interest. Its hydrolysis was examined at temperatures ranging from 13 to 59°C. Phosgene itself was generated by radiolysis of aqueous CCl4 solutions [Eq. (a)].

      • equation image
    12. Determination of the Kinetics of Vinyl Radical Reactions by the Characteristic Visible Absorption Spectra of Vinylperoxyl Radicals (pages 1262–1264)

      Dipl.-Chem. Ralf Mertens and Prof. Dr. Clemens von Sonntag

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412621

      Thumbnail image of graphical abstract

      Vinylperoxyl radicals surprisingly absorb in the visible region, whereas other peroxyl radicals absorb in the UV. Thus the kinetics of reactions of both vinylperoxyl radicals and vinyl radicals can be studied conveniently. The peroxyl radicals are formed by pulse radiolysis of oxygen-containing aqueous solutions of vinyl halides like 1 [Eq. (a)].

    13. Oxygen-Induced Structural Transformation of the Polynuclear Organoaluminum Complex [Al43-8-quinolylimide)2(CH3)8] to [Al43-8-quinolylimide)2(CH3)7(μ-OCH3)] (pages 1265–1266)

      Steven J. Trepanier and Prof. Dr. Suning Wang

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412651

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      A change from a butterfly structure to a tetrahedral arrangement is triggered in the Al4 framework by the oxidation of 1 to 2 in toluene at 23°C. Remarkably, only one methyl group of 1 is oxidized; 2 is stable for several days in solution.

    14. The First Cycloaddition Reactions of Dimeric Arsenium Cations (pages 1267–1268)

      Neil Burford, Trenton M. Parks, Pradip K. Bakshi and T. Stanley Cameron

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412671

      Thumbnail image of graphical abstract

      The bic̀yclic cations 1 and 2 are formed in the reactions of the dimeric arsenium ions 3 and 4, respectively, with 2,3-dimethylbuta-l,3-diene. These cycloadditions can be interpreted as Diels–Alder reactions in which the heteroatom–arsenic bond is formally considered a double bond; the analogous phosphenium ions react differently. Counterion: GaClmath image.

    15. Metalation of Tris(trimethylsilyl)- and Tris(dimethylphenylsilyl)methane with Methylsodium: The First Dialkylsodate (pages 1268–1270)

      Dr. Salih S. Al-Juaid, Prof. Colin Eaborn, Dr. Peter B. Hitchcock, Dr. Keith Izod, Dr. Michael Mallien and Dr. J. David Smith

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412681

      A two-coordinate sodium atom is present in the linear diorganosodate anion in 1, obtained by metalation of the relevant trisilylmethane with sodium in the presence of tmen (N,N,N′,N′-tetramethylethylenediamine); the corresponding reaction with tris(dimethylphenylsilyl)methane in the absence of the chelating ligand yields 2, which has a distorted tetrahedral environment about the sodium atom and an unprecedented chain structure.

      • equation image
    16. Efficient Synthesis of Heteroradialenes by SN′ Reaction (pages 1270–1272)

      Prof. Dr. Rolf Gleiter, Dipl.-Chem. Harald Röckel, Prof. Dr. Hermann Irngartinger and Dr. Thomas Oeser

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412701

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      Permethylated heteroradialenes are excellent candidates for donor components in donor–acceptor complexes because of their electronic properties. The thiaradialenes 1 and 2 and the expanded thiaradialene 3 were synthesized in an astonishingly easy way. Results of photoelectron spectroscopy and cyclic voltammetry show that compounds 1 and 2 are indeed electron-rich π systems.

    17. New Types of Metal-Stabilized Cyclobutadiene Superphanes (pages 1272–1274)

      Prof. Dr. Rolf Gleiter, Dipl.-Chem. Heinrich Langer and Dr. Bernhard Nuber

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412721

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      The surprising intramolecular [4 + 2]-cycloaddition of a cobaltacyclopentadiene to a complexed cyclobutadiene is the key step of the synthesis of the superphane 1. Furthermore, novel superphanes like 2 can be constructed from tricyclic diketones.

    18. Micrometer-Scale Lateral Structuring of Organic Thiolate Layers through Self-Organization (pages 1274–1276)

      Dr. Claus Duschl, Dr. Martha Liley and Dr. Horst Vogel

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412741

      Thumbnail image of graphical abstract

      The combined application of both Langmuir–Blodgett and self-assembly techniques allows the formation of laterally structured thiolate films on gold surfaces with domains of contrasting surface properties. These monolayers with areas of amphiphilic disulfides and others of mercaptocarboxylic acids, each covalently bound, can be used for the selective formation of multilayers of copper thiol complexes (shown schematically on the right). The principle of this technique can also be applied to other fields, for example, biochemistry.

    19. A New Method for the Synthesis of Heterometallic Complexes: Syntheses and Structures of [(PhCH2CH2NLi)3Sb(thf)]2 and [Sb3(cyN)4(NMe2)2]Li (pages 1277–1279)

      Dr. Andrew J. Edwards, Michael A. Paver, Dr. Paul R. Raithby, Moira-Ann Rennie, Christopher A. Russell and Dr. Dominic S. Wright

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412771

      Successive metalation of primary amines, first with nBuLi and then with Sb(NMe2)3, has enabled the preparation of the heterometallic complexes 1 and 2. Neutra [Ph(CH2)2N(H)Li]n and ionic Li[Sb(cyNH)4] occur as the intermediates in the formation of 1 and 2, respectively.

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    20. On the Mechanism of the Urocanase Reaction: Confirmation of the Structure of the NAD+-Inhibitor Adduct by Direct 13C-13C Coupling (pages 1279–1280)

      Dipl.-Chem. Carsten Schubert, Dr. Ymin Zhao, Prof. Dr. Jung-Hyn Shin and Prof. Dr. János Rétey

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412791

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      NAD+ functions not as a redox reagent but as an electrophile in the second step in the degradation of histidine. In this as yet unique enzymatic reaction, water is added to urocanic acid (1), leading to the formation of 2. The proposed mechanism has now been substantiated by NMR spectroscopic results on the 13C-labeled adduct 3. R = ADP-ribosyl, • = 13C.

    21. Cyclopropanes by Nucleophilic Attack of Mono-and Diaryl-Substituted (η3-Allyl)palladium Complexes: Aryl Effect and Stereochemistry (pages 1280–1282)

      Dipl.-Chem. Andreas R. Otte, Dr. Andreas Wilde and Prof. Dr. H. M. R. Hoffmann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412801

      Thumbnail image of graphical abstract

      A series of cis-diphenylated cyclopropanes has been introduced into the C-H acidic position of a range of nucleophiles, for example, deprotonated esters and acid amides, ketones, and sulfones. In these reactions bis[(η3-l,3-diphenylallyl)palladium] complexes serve as electrophiles, and products such as 1 form. Quaternary carbon centers exocyclic to the newly formed three-membered ring are installed with ease.

    22. Copper(II)-Mediated Oxidative Coupling of Bis(dimethylaminomethyl)arylruthenium Complexes to give [(terpy)RuIII(pincer-pincer)-RuIII(terpy)](CuCl2)4 (pages 1282–1285)

      Dr. Jean-Pascal Sutter, Dr. David M. Grove, Dr. Marc Beley, Dr. Jean-Paul Collin, Nora Veldman, Dr. Anthony L. Spek, Dr. Jean-Pierre Sauvage and Prof. Dr. Gerard van Koten

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412821

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      A completely conjugated π system with participation of the Ru centers characterizes the cationic complex 14 +, which was formed from the analogous mononuclear RuII complex by selective C4-C4′ coupling. This is confirmed by crystallographic and NMR spectroscopic findings as well as the fact that strong electronic communication is displayed between RuII and RuIII in 13+.

    23. Molecular Siloxane Complexes of Rare Earth Metals—Model Systems for Silicate-Supported Catalysts? (pages 1285–1286)

      Prof. Dr. Wolfgang A. Herrmann, Dr. Reiner Anwander, Dr. Veronique Dufaud and Wolfgang Scherer

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412851

      Thumbnail image of graphical abstract

      Participation of the oxygen atoms of the siloxane framework of ligand 1, and not only the terminal hydroxyl groups, may be required for the coordinative saturation of a metal center. This surprising conclusion was drawn from the X-ray structure analysis of the first rare earth metal complex with this type of ligand. Compound 1 serves as a molecular model for SiO2 supports for transition metal catalysts.

    24. Olympiadane (pages 1286–1290)

      Dr. David B. Amabilino, Peter R. Ashton, Dr. Anatoli S. Reder, Dr. Neil Spencer and Prof. J. Fraser Stoddart

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412861

      Thumbnail image of graphical abstract

      Five interlocked rings in a linear arrangement form the familiar symbol of the Olympic Games and also describe olympiadane, a [5]catenane which was assembled from eight components in two steps at ambient temperature and pressure. This self-assembly process is possible as sufficient molecular recognition was programmed into the components. The fragmentation patterns in the mass spectrum and the 1H NMR spectrum support the structure shown schematically on the right.

    25. [Cu96P30{P(SiMe3)2}6(PEt3)18], a New Phosphorus-Bridged Copper Cluster (pages 1290–1292)

      Prof. Dr. Dieter Fenske and Dipl.-Chem. Werner Holstein

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412901

      One of the largest cluster complexes whose structure has been elucidated is the title compound, which is formed from CuCl, PEt3, and P(SiMe3)3, when the components are used in the ratio 1:0.5:0.6. The structure, which is difficult to describe, can be discussed as an intermediate in the formation of binary Cu3P.

    26. An Organic Molecule with a Rigid Cavity of Nanosize Dimensions (pages 1292–1295)

      Drs. Peter Timmerman, Dr. Willem Verboom, Dr. Ir. Frank C. J. M. van Veggel, Ir. Willem P. van Hoorn and Prof. Dr. Ir. David N. Reinhoudt

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412921

      Thumbnail image of graphical abstract

      An internal volume of approximately 1000 Å3 is available in the permanent cavity of a new rigid host molecule (shown on the right). The holand was assembled in six reaction steps by the fusion of four cavities of two calix[4]arene and two resorcin[4]arene building blocks, which are connected by amide spacers. This host is expected to show novel complexation properties.

    27. A New Synthesis of 1,3,4-Trideoxy-1,4-iminoglycitols of Varying Chain Length by (C3 + Cn)-Coupling of Allyl Halides with Glycononitrile Oxides (pages 1295–1298)

      Dr. Rudolf Müller, Dipl.-Chem. Thomas Leibold, Dr. Michael Pätzel and Prof. Dr. Volker Jäger

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412951

      Thumbnail image of graphical abstract

      With the “correct” combination of 3- and 5-substituents and the appropriate catalyst the C[DOUBLE BOND]N/N[BOND]O hydrogenation of isoxazolines 1 proceeds with high stereoselectivity to yield hydroxypyrrolidines 2 with variable side chains in one step, by two-fold reduction and recyclization, as shown in the example in Equation (a).

    28. Simple and Versatile Synthesis of Optically Active 1,2-Amino Alcohols by Grignard Addition to N,O-Dibenzylglyceraldimine and -lactaldimine (pages 1298–1301)

      Dr. Thomas Franz, Dipl.-Chem. Matthias Hein, Dipl.-Chem. Ulrich Veith, Prof. Dr. Volker Jäger, Eva-Maria Peters, Dr. Karl Peters and Prof. Dr. Hans Georg von Schnering

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199412981

      Thumbnail image of graphical abstract

      In many cases with high threo selectivity, Grignard additions can be performed on simple, nonactivated, and even enolizable imine derivatives of optically active aldehydes, as the reactions with 1 and 2 show. This should open a new route to aminohydroxy acids that supplements the familiar one starting from α-amino acids/aldehydes.

  3. Book Reviews

    1. Top of page
    2. Reviews
    3. Communications
    4. Book Reviews
    1. Book Review: Unraveling DNA. By M. D. Frank-Kamenetskii (pages 1303–1304)

      Siegfried Hoffmann

      Version of Record online: 22 DEC 2003 | DOI: 10.1002/anie.199413032

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