European Journal of Organic Chemistry

Cover image for Vol. 2013 Issue 18

June 2013

Volume 2013, Issue 18

Pages 3604–3918

  1. Cover Picture

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. You have free access to this content
      Macrocyclic Effects in the Mesomorphic Properties of Liquid-Crystalline Pillar[5]- and Pillar[6]arenes (Eur. J. Org. Chem. 18/2013)

      Iwona Nierengarten, Sebastiano Guerra, Michel Holler, Lydia Karmazin-Brelot, Joaquín Barberá, Robert Deschenaux and Jean-François Nierengarten

      Article first published online: 13 JUN 2013 | DOI: 10.1002/ejoc.201390049

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      The cover picture shows the thermal polarized optical micrograph of the texture displayed by a pillar[5]arene derivative substituted with ten mesogenic subunits as well as the postulated supramolecular arrangement of the macrocyclic molecules in the smectic A phase. Details are discussed in the article by J. Barberá, R. Deschenaux, J.-F. Nierengarten et al. on page 3675 ff..

  2. Graphical Abstract

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
  3. News

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
  4. Microreview

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. Nazarov Cyclization

      Beyond the Divinyl Ketone: Innovations in the Generation and Nazarov Cyclization of Pentadienyl Cation Intermediates (pages 3621–3633)

      William T. Spencer III, Tulaza Vaidya and Alison J. Frontier

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300134

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      Nazarov electrocyclization is a synthetic method for the preparation of functionalized five-membered rings, often in a stereospecific manner. This review highlights innovative strategies for gaining access to the key pentadienyl cation intermediates and illustrates how these new approaches have expanded the scope and utility of the reaction.

  5. Short Communications

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. Fluorescent Probes

      (E)-2-Cyano-3-(5′-piperidin-1-yl-2,2′-bithien-5-yl)acrylic Acid: A Fluorescent Probe for Detecting Prefibrillar Oligomers (pages 3635–3639)

      Francesco Attanasio, Carmela Bonaccorso, Francesco Bellia, Sebastiano Cataldo, Cosimo G. Fortuna, Giuseppe Musumarra, Bruno Pignataro and Enrico Rizzarelli

      Article first published online: 29 APR 2013 | DOI: 10.1002/ejoc.201300241

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      (E)-2-Cyano-3-(5′-piperidin-1-yl-2,2′-bithien-5-yl)acrylic acid (p-TTCNAc) can be conveniently used as a fluorescent probe to identify prefibrillar oligomers of hen egg white lysozyme not detected by Thioflavin-T (ThT).

    2. Metallomacromolecules

      Perylene-Based Bis-, Tetrakis-, and Hexakis(terpyridine) Ligands and Their Ruthenium(II)–Bis(terpyridine) Complexes: Synthesis and Photophysical Properties (pages 3640–3644)

      Hany El-Batal, Kai Guo, Xiaopeng Li, Chrys Wesdemiotis, Charles N. Moorefield and George R. Newkome

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300329

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      A family of functional materials bearing a perylene core and terpyridine branches, along with their RuII–bis(terpyridine) complexes, was designed and synthesized. Their structures were elucidated by NMR spectroscopy and MS. Their optical properties showed absorption spectra that ranged from 250 to 625 nm, which suggests their possible use as sensitizers for dye-sensitized solar cells.

    3. Amino Acids

      Synthesis of Optically Active Selenium-Containing Isotryptophan, Homoiso­tryptophan, and Homotryptophan (pages 3645–3647)

      Koushik Goswami, Amrita Chakraborty and Surajit Sinha

      Article first published online: 7 MAY 2013 | DOI: 10.1002/ejoc.201300352

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      Selenium analogues of isotryptophan and homoisotryptophan derivatives were synthesized by Sonogashira coupling of iodophenyl methyl selenide with alkynyloxazolidines followed by iodocyclization as the key step. Sonogashira coupling of 3-iodobenzoselenophene with ethynyloxazolidine afforded the selenohomotryptophan derivative.

    4. Olefination

      Oxidative Olefination of Secondary Amines­ with Carbon Nucleophiles (pages 3648–3652)

      Yong-Gang Zhang, Jing-Kun Xu, Xi-Ming Li and Shi-Kai Tian

      Article first published online: 6 MAY 2013 | DOI: 10.1002/ejoc.201300368

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      A range of secondary N-alkylanilines smoothly underwent DDQ-promoted oxidative olefination with 2-alkylazaarenes, acetophenone, and malononitrile to give structurally diverse alkenes in moderate to excellent yields with excellent (E) selectivity. Mechanistically, the reaction proceeds through amine oxidation followed by imine olefination (DDQ = 2,3-dichloro-5,6-dicyano-1,4-benzoquinone).

    5. Cyclic Aminophosphonates

      Synthesis of Azaheterocyclic Vinylphosphonates by Ring-Closing Metathesis (pages 3653–3657)

      Cécile Garzon, Mireille Attolini and Michel Maffei

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300375

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      Organocatalysis and ring-closing metathesis enable a two-step synthesis of azaheterocyclic vinylphosphonates, giving access to five- and six-membered ring compounds. The required (ω-alkenyl) p-toluenesulfonamides were obtained through the Mitsunobu reaction, which allows the synthesis of chiral phosphonates.

    6. Dehydrogenation

      Dehydrogenation of Perfluoroalkyl Ket­ones by Using a Recyclable Oxoammonium Salt (pages 3658–3661)

      Trevor A. Hamlin, Christopher B. Kelly and Nicholas E. Leadbeater

      Article first published online: 7 MAY 2013 | DOI: 10.1002/ejoc.201300392

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      The dehydrogenation of perfluoroalkyl ketones by using an oxoammonium salt is reported. The reaction proceeds under mildly basic conditions and affords α,β-unsaturated products in fair to excellent yields. The reaction likely proceeds through a two-step sequence. The spent oxidant can easily be recovered and used to regenerate the oxoammonium salt.

    7. Onium Ylides

      In Situ Generation Technology of β-But­oxycarbonyliodonium Ylide: A Hyperva­lent Analogue of the Darzens Reagent (pages 3662–3666)

      Kazunori Miyamoto, Mai Suzuki, Takashi Suefuji and Masahito Ochiai

      Article first published online: 6 MAY 2013 | DOI: 10.1002/ejoc.201300413

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      The reactivity of monoester iodonium ylide is investigated. Highly labile mono ester iodonium ylide generated in situ from β-butoxy-β-acyloxyvinyl-λ3-iodane through an ester exchange reaction cleanly undergoes Darzens-type condensation with aromatic aldehydes to afford trans-epoxy ester selectively.

    8. Aminohydroxylation

      Stereocontrolled Synthesis of 1,3-Diamino-2-ols by Aminohydroxylation of Bicyclic Methylene-Aziridines (pages 3667–3670)

      Cale D. Weatherly, Ilia A. Guzei and Jennifer M. Schomaker

      Article first published online: 6 MAY 2013 | DOI: 10.1002/ejoc.201300416

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      Complex amine-containing stereotriads are recurring motifs in a number of bioactive and pharmacologically important molecules. The regio- and stereocontrolled aminohydroxylation of bicyclic methylene-aziridines can be followed by carbonyl reduction to deliver 1,3-diamino-2-ols in good yields with good diastereoselectivities (Ts = para-tolylsulfonyl, Bs = phenylsulfonyl, Boc = tert-butoxycarbonyl).

    9. Reductive N-Monoalkylation

      Ruthenium-Catalyzed Transfer Hydrogenation of Nitriles: Reduction and Subsequent N-Monoalkylation to Secondary Amines (pages 3671–3674)

      Svenja Werkmeister, Christoph Bornschein, Kathrin Junge and Matthias Beller

      Article first published online: 26 APR 2013 | DOI: 10.1002/ejoc.201300151

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      A simple method for the synthesis of secondary amines starting directly from nitriles by using a ruthenium catalyst is described. With this novel domino system, various nitriles were reduced and subsequently N-monoalkylated in excellent yields (up to 99 %). In addition to isopropanol, other alcohols were also used as a reductant and N-monoalkylation reagent.

  6. Full Papers

    1. Top of page
    2. Cover Picture
    3. Graphical Abstract
    4. News
    5. Microreview
    6. Short Communications
    7. Full Papers
    1. Liquid Crystals

      Macrocyclic Effects in the Mesomorphic Properties of Liquid-Crystalline Pillar[5]- and Pillar[6]arenes (pages 3675–3684)

      Iwona Nierengarten, Sebastiano Guerra, Michel Holler, Lydia Karmazin-Brelot, Joaquín Barberá, Robert Deschenaux and Jean-François Nierengarten

      Article first published online: 29 APR 2013 | DOI: 10.1002/ejoc.201300356

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      Pillar[n]arene (n = 5 or 6) derivatives substituted with peripheral mesogenic moieties gave rise to an enantiotropic smectic A phase over a very broad temperature range, whereas only a monotropic mesophase was observed for the corresponding constitutive acyclic monomeric subunit.

    2. Supramolecular Chemistry

      ZnII-Cyclen as a Supramolecular Probe for Tagging Thymidine Nucleosides on Carbon Nanotubes (pages 3685–3690)

      Alessandra Micoli, M. Laura Soriano, Hassan Traboulsi, Mildred Quintana and Maurizio Prato

      Article first published online: 25 APR 2013 | DOI: 10.1002/ejoc.201300075

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      The ZnII-cyclen macrocycle is revealed to be an efficient and selective molecular probe for tagging thymidine (Td) nucleoside functionalities covalently linked to multiwalled carbon nanotubes (MWCNTs).

    3. NHC-Appended Cyclodextrins

      Diametrically Opposed Carbenes on an α-Cyclodextrin: Synthesis, Characterization of Organometallic Complexes and Suzuki–Miyaura Coupling in Ethanol and in Water (pages 3691–3699)

      Maxime Guitet, Filipa Marcelo, Ségolène Adam de Beaumais, Yongmin Zhang, Jesús Jiménez-Barbero, Sébastien Tilloy, Eric Monflier, Mickaël Ménand and Matthieu Sollogoub

      Article first published online: 18 APR 2013 | DOI: 10.1002/ejoc.201300190

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      Two carbene-based ligands have been attached to perbenzylated and permethylated cyclodextrins. Their palladium complexes were synthesized, characterized and used as catalysts in Suzuki–Miyaura coupling reactions both in ethanol and water.

    4. Porphyrinoids

      Synthesis and Functionalization of Triply Fused Porphyrin Dimers (pages 3700–3711)

      Aoife A. Ryan and Mathias O. Senge

      Article first published online: 19 APR 2013 | DOI: 10.1002/ejoc.201201622

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      A library of symmetric and unsymmetric singly linked and triply fused porphyrin dimers are synthesized in moderate to very good yields. A variety of functional groups are tolerated. Numerous synthetic strategies, incorporating oxidative radical coupling and organolithium and palladium-catalyzed coupling methods, are utilized.

    5. Strained Molecules in Cycloaddition

      Electronic Effects versus Distortion Energies During Strain-Promoted Alkyne-Azide Cycloadditions: A Theoretical Tool to Predict Reaction Kinetics (pages 3712–3720)

      Jaime Garcia-Hartjes, Jan Dommerholt, Tom Wennekes, Floris L. van Delft and Han Zuilhof

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201201627

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      Activation energies, distortion energies, and TS conformational data were compared in a set of strained cyclooctynes in strain-promoted azide–alkyne cycloaddition (SPAAC) reactions. Only electronic effects could be accurately related to experimental rate data.

    6. Triazole Tautomerism

      Tautomerism in the Fused N-Rich Tri­azolotriazole Heterocyclic System (pages 3721–3728)

      Roberto Centore, Sandra Fusco, Amedeo Capobianco, Vincenzo Piccialli, Sabrina Zaccaria and Andrea Peluso

      Article first published online: 19 APR 2013 | DOI: 10.1002/ejoc.201201653

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      [1,2,4]Triazolo[3,2-c][1,2,4]triazole has three tautomers: 2H, 3H and 5H. It is shown that the most stable tautomer is 2H, tautomer 3H has intermediate energy and the 5H has the highest energy. This compound provides a striking counter-example of the generally held view that the organic conjugated structure with the highest number of alternating single and double bonds is the most stable.

    7. Platinum Acetylides

      Platinum(II) Acetylides in the Formal [2+2] Cycloaddition-Retroelectrocyclization Reaction: Organodonor Versus Metal Activation (pages 3729–3740)

      Boris H. Tchitchanov, Melanie Chiu, Markus Jordan, Milan Kivala, W. Bernd Schweizer and François Diederich

      Article first published online: 26 APR 2013 | DOI: 10.1002/ejoc.201300300

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      Donor-activated triple bonds act as substrates for cycloaddition-retroelectrocyclization reactions with TCNE or TCNQ to give cyanobutadienes. Herein we showcase the activation ability of two classes of donors: organic amines and platinum(II) centers directly bound to the acetylenic moieties and compare them directly for the first time.

    8. Ionic Liquids

      Ionic Liquids Based on the 7-Azabicyclo[2.2.1]heptane Skeleton: Synthesis and Properties (pages 3741–3750)

      Nils De Vos, Cedric Maton, Peter De Vreese, Neil R. Brooks, Koen Binnemans and Christian V. Stevens

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300338

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      Ionic liquids with the cationic part based on the structure of epibatidine (a 7-azabicyclo[2.2.1] skeleton) have been prepared. The chemical and physical properties of these ionic liquids with dicyanamide and bis(trifluoromethylsulfonyl)imide anions were investigated and they were found to show very good electrochemical and thermal stability.

    9. Bioactive Natural Products

      Cytotoxic and Antimicrobial Napyradiomycins from Two Marine-Derived Streptomyces Strains (pages 3751–3757)

      Yuan-Bin Cheng, Paul R. Jensen and William Fenical

      Article first published online: 30 APR 2013 | DOI: 10.1002/ejoc.201300349

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      The cancer-cell-cytotoxicity-guided fractionation of the acetone extracts of two cultured marine-derived Streptomyces strains yields six new napyradiomycins (16). Napyradiomycins 14 are new members of the napyradiomycin “C-type” meroterpenoids, which possess a linear monoterpene bridge between C-7 and C-10a. The cytotoxicity and antibacterial activities of 16 are presented.

    10. Dithiocarbamates

      Synthesis of S- and N-Functionalized Dithiocarbamates from Cyclic Sulfates (pages 3758–3763)

      Jose Parada-Aliste, Alicia Megia-Fernandez, Diego De la Torre-Gonzalez, Fernando Hernandez-Mateo and Francisco Santoyo-Gonzalez

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201201522

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      As an efficient route to dithiocarbamates, a simple and versatile method for preparing S- and N-functionalized dithiocarbamates starting for readily available cyclic sulfates and commercial amines under environmentally friendly conditions is reported.

    11. Sulfamidate Heterocycles

      Phosphane-Catalyzed [3+2] Cycloaddition Reaction of Allenoate and Cyclic Imines: A Simple and Efficient Method for Synthesis of Benzo-Fused Cyclic Sulfamidate Heterocycles (pages 3764–3770)

      You-Qing Wang, Yongna Zhang, Haina Dong, Jie Zhang and Jin Zhao

      Article first published online: 22 APR 2013 | DOI: 10.1002/ejoc.201201756

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      Benzo-fused cyclic sulfamidate heterocycles have been synthesized in 71–97 % yields through a cycloaddition reaction of allenoate with cyclic imines (various aldimines and a trifluoromethyl ketimine) by using PPh3 as organocatalyst. After screening several commercially available chiral phosphanes, up to 36 % ee was obtained with (R)-H8-BINAP.

    12. Lipooligosaccharides

      Structural Characterization of the Core Oligosaccharide Isolated from the Lipo­polysaccharide of the Psychrophilic Bacterium Colwellia psychrerythraea Strain 34H (pages 3771–3779)

      Sara Carillo, Giuseppina Pieretti, Buko Lindner, Ermenegilda Parrilli, Sannino Filomena, Maria Luisa Tutino, Rosa Lanzetta, Michelangelo Parrilli and Maria Michela Corsaro

      Article first published online: 26 APR 2013 | DOI: 10.1002/ejoc.201300005

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      The structural characterization of the lipooligosaccharide from the steno-psychrophilic bacterium Colwellia psychrerythraea strain 34H has been achieved by means of chemical analysis, mass spectrometry, and NMR spectroscopy experiments. The data revealed a very short, negatively charged, and unique oligosaccharide, lacking heptose residues.

    13. Heterocyclic Synthesis

      Synthesis of 5-Organotellanyl-1H-1,2,3-tri­azoles: Functionalization of the 5-Position Scaffold by the Sonogashira Cross-Coupling Reaction (pages 3780–3785)

      Hélio A. Stefani, Stanley N. S. Vasconcelos, Flávia Manarin, Daiana M. Leal, Frederico B. Souza, Lucas Sousa Madureira, Julio Zukerman-Schpector, Marcos N. Eberlin, Marla N. Godoi and Renan de Souza Galaverna

      Article first published online: 24 APR 2013 | DOI: 10.1002/ejoc.201300009

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      An efficient synthesis of 5-organotellanyl-1H-1,2,3-triazole compounds through [3+2] cycloaddition reaction of organic azides and (organotellanyl)alkynes is presented. The 5-organotellanyl-1H-1,2,3-triazoles were readily functionalized at the 5-position to give highly functionalized triazoles.

    14. Total Synthesis

      Alkyne-Mediated Approach for Total Syntheses of Cladospolides A, B, C and iso-Cladospolide B (pages 3786–3796)

      Chada Raji Reddy, Devatha Suman and Nagavaram Narsimha Rao

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300022

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      A common alkyne-mediated approach to the total syntheses of cladospolides A, B, and C and iso-cladospolide B was accomplished by using an alkyne-zipper reaction, a Sharpless asymmetric epoxidation/dihydroxylation, and a Yamaguchi macrolactonization as the key steps.

    15. Tandem Reactions

      Three-Component Tandem-Intramolecular Hydroamination Reactions in One Pot Involving Indoles, 2-Aminobenzyl Alcohols, and 2-Alkynylbenzaldehydes: Consecutive 7-endo-trig and Electrophilic 6-endo-dig Cyclizations (pages 3797–3806)

      Srinivas Samala, Mohammad Saifuddin, Anil K. Mandadapu and Bijoy Kundu

      Article first published online: 19 APR 2013 | DOI: 10.1002/ejoc.201300100

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      A one-pot three-component tandem reaction with a subsequent intramolecular hydroamination reaction was applied to generate libraries of benzazepino-indole and isoquinolino-benzazepino-indole derivatives.

    16. Radical Photochemistry

      Photochemical C–C Bond Formation between Alcohols and Olefins by an Environmentally Benign Radical Reaction (pages 3807–3816)

      Akihiko Ouchi, Chuanxiang Liu, Masayuki Kaneda and Takeshi Hyugano

      Article first published online: 25 APR 2013 | DOI: 10.1002/ejoc.201300115

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      A radical C–C bond formation between olefins and alcohols proceeded efficiently by simple light irradiation at room temperature without using the harmful elements often used in conventional radical reactions.

    17. Ring-Rearrangement Metathesis

      Ring-Rearrangement Metathesis of 7-Aza­norbornenes as an Entry to 1-Azabicyclo[n.3.0]alkenones (pages 3817–3824)

      Víctor Rojas, Javier Carreras, Alberto Avenoza, Jesús H. Busto and Jesús M. Peregrina

      Article first published online: 18 APR 2013 | DOI: 10.1002/ejoc.201300126

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      A new synthetic strategy for nitrogen heterocycles was developed that incorporates fused-ring systems and takes advantage of a stereodefined ring-rearrangement metathesis process of substituted 7-azanorbornenes as the stereocontrolled key step. A set of new 1-azabicyclo[n.3.0]alkenones (n = 3, 4, and 5) that include new analogues of pyrrolam were prepared by using this methodology.

    18. Blue Light-Emitting Diodes

      Synthesis and Characterization of 9-(Fluoren­-2-yl)anthracene Derivatives as Efficient Non-Doped Blue Emitters for Organic Light-Emitting Diodes (pages 3825–3834)

      Narid Prachumrak, Supawadee Namuangruk, Tinnagon Keawin, Siriporn Jungsuttingwong, Taweesak Sudyoadsuk and Vinich Promarak

      Article first published online: 25 APR 2013 | DOI: 10.1002/ejoc.201300165

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      New 9-(fluoren-2-yl)anthracene derivatives with combined blue-light-emitting and hole-transporting characteristics have been developed that exist in a stable amorphous state and deliver high fluorescence quantum yields.

    19. Carbanucleosides

      Syntheses of New Carbanucleosides by Pericyclic Reactions (pages 3835–3846)

      Luca Scagnelli, Misal Giuseppe Memeo, Serena Carosso, Bruna Bovio and Paolo Quadrelli

      Article first published online: 30 APR 2013 | DOI: 10.1002/ejoc.201300202

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      The synthesis of heterobase-functionalized cyclopentene derivatives as valuable substrates for the introduction of suitable substituents through pericyclic reactions is reported. The structures of ene and 1,3-dipolar adducts are discussed, and the primary antiviral activities of some adenine derivatives are reported.

    20. Phenanthridine Synthesis

      Photochemical Synthesis of Phenanthridines: Exploring Fluoro and Protected Catechol Substitution (pages 3847–3856)

      Anna M. Linsenmeier, Craig M. Williams and Stefan Bräse

      Article first published online: 10 MAY 2013 | DOI: 10.1002/ejoc.201300218

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      Substituted phenanthridines, such as the natural product trispheridine, can be accessed by the practical photochemical cyclization of N-benzylanilines, with functionalities tolerated on both the A and C rings. The phenanthridines are accessible in good to very good yields (up to 95 %) from iodinated substrates, whereas brominated substrates perform poorly in comparison (0–48 %).

    21. Cucurbituril Derivatives

      Synthesis of Cucurbit[6]uril Derivatives and Insights into Their Solubility in Water (pages 3857–3865)

      Véronique Lewin, Julie Rivollier, Sylvie Coudert, David-Alexandre Buisson, Delphine Baumann, Bernard Rousseau, François-Xavier Legrand, Hana Kouřilová, Patrick Berthault, Jean-Pierre Dognon, Marie-Pierre Heck and Gaspard Huber

      Article first published online: 26 APR 2013 | DOI: 10.1002/ejoc.201300229

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      New molecules derived from cucurbit[6]uril with either a propanediurea unit or cyclohexane moieties have been synthesized. Their solubility in pure water increased with the number of these nonclassical units. This can be explained in terms of changes in intermolecular C–H···O hydrogen bonding rather than in the molecular shape.

    22. Chiral Allene Synthesis

      Enantioselective Synthesis of Both Enantio­mers of Chiral Allenes Using Chiral N-Methylcamphanyl Piperazine Templates (pages 3866–3875)

      Mariappan Periasamy, Polimera Obula Reddy and Nalluri Sanjeevakumar

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300231

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      A new method for the synthesis of both isomers of chiral 1,3-disubstituted allenes with enantiomeric purity up to 99 % ee, using selectively alkylated chiral camphanyl-piperazines, aldehydes, terminal alkynes, and ZnBr2 has been developed.

    23. Porphyrin Chemistry

      Expansion of a Pyrrole in meso-Tetra­phenylporphyrin to a Pyrazine Imide Moiety­ Using a Beckmann Rearrangement (pages 3876–3884)

      Joshua Akhigbe and Christian Brückner

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300274

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      A Beckmann reaction of a porphyrindione monooxime is used to expand a pyrrole to a pyrazine imide moiety within the porphyrin and generate a new pyrrole-modified porphyrin-like compound that contains a six-membered heterocycle. The imide functionality can serve as a synthetic handle for further manipulations of the chromophore.

    24. Aminoalkylation of Indoles

      Leaving Group and Regioselectivity Switches in the Aminoalkylation Reaction of Indoles and Related Heterocycles with α-Amido Sulfones (pages 3885–3895)

      Gonzalo Blay, Rosa M. Girón, Marc Montesinos-Magraner and José R. Pedro

      Article first published online: 5 MAY 2013 | DOI: 10.1002/ejoc.201300369

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      The regioselective aminoalkylation of indoles and heterocycles with α-amido sulfones under basic conditions is described. The reaction with MeMgBr/MgBr2 gives 3-(1-carbamoylalkyl)indoles, whereas employing Cs2CO3 yields 1-(1-carbamoylalkyl)indoles. The first case presents a switch of the leaving group of the α-amido sulfone, whereas the second demonstrates a switch in the regioselectivity.

    25. Nucleophilic Cyanide addition

      Solvent-Assisted Diastereoselective Tri­meth­ylsilyl Cyanide Additions to Cyclic α-Fluoro Ketones (pages 3896–3900)

      Hao Pham and Todd A. Davis

      Article first published online: 23 APR 2013 | DOI: 10.1002/ejoc.201201637

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      A method for the trimethylsilyl cyanide (TMSCN) addition to α-fluoro ketones has been developed, giving the nitrile products in high yields and with good to modest stereoselectivities. TMSCN is activated in strongly electron-donating solvents, such as DMF, to produce the fluorinated TMS-protected cyanohydrin in yields of up to 95 % and diastereoselectivities as high as 22:1.

    26. Chiral β-Lactams

      Synthesis of Chiral Spirocyclopentenyl-β-lactams through Phosphane-Catalyzed [3+2] Annulation of Allenoates with 6-Alkylidenepenicillanates (pages 3901–3909)

      Bruna S. Santos and Teresa M. V. D. Pinho e Melo

      Article first published online: 26 APR 2013 | DOI: 10.1002/ejoc.201300153

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      The first examples of phosphane-catalyzed [3+2] annulation of allenoates to 6-alkylidenepenicillanates leading to chiral spirocyclopentenyl-β-lactams are reported. The process involves the generation of either two or three consecutive stereogenic centers, including a quaternary chiral center.

    27. C–H Functionalization

      A General Procedure for the Regioselective Synthesis of Aryl Thioethers and Aryl Selenides Through C–H Activation of Arenes (pages 3910–3918)

      Chih-Lun Yi, Tsung-Jui Liu, Jun-Hao Cheng and Chin-Fa Lee

      Article first published online: 18 APR 2013 | DOI: 10.1002/ejoc.201300248

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      Aryl thioethers and selenides were prepared in good yields with high meta regioselectivity through sequential Ir-catalyzed C–H borylation and Cu-promoted C–S and C–Se bond formation in one pot. A wide range of functional groups were tolerated under the reaction conditions. In addition to aryl thiols and selenides, alkyl thiols and selenides were also suitable coupling partners in this reaction.

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