Letters in Organic Chemistry

ISSN: 1570-1786

Letters in Organic Chemistry,
Volume 2, Number 7, November 2005

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Letters in Organic Chemistry

Synthesis and Cation Binding Properties by 5,11,17,23-Tetra(Tert-Butyl)-25,27- Bis(Ethoxymethoxy)-26,28-Bis (Diethylaminocarbonylmethoxy)calix[4] Arene

B. Mellah, L. Baklouti, R. Abidi & J. Vicens Facultés des Sciences de Bizerte, 7021 Zarzouna-Bizerte, Tunisia ECPM, Université Louis Pasteur, associé au CNRS, 25 rue Becquerel F-67087, Strasbourg, France We report the preparation of 5,11,17,23-tetra(tert-butyl) -25,27-bis(ethoxymethoxy)-26,28-bis (diethylaminocarbonylmethoxy)calix[4]arene 1 and its binding properties towards alkali and alkaline-earth cations.

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A Simple Preparation of Dihydrofullerene and Its Reversion to Fullerene (C60)

G.-W. Wang, Y.-J. Li, F.-B. Li & Y.-C. Liu Hefei National Laboratory for Physical Sciences at Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China C60H2 was prepared in high yield by the reduction of C60 with either NaBH4 or Hantzsch esters. Dehydrogenation of hydrofullerenes to C60 by both organic and inorganic bases in the presence of air was achieved in 90-99% yield.

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New Synthesis of Pyrazolyl-1,3,4-Oxadiazole and 1,3,4-Oxadiazoline Derivatives

B. Cottineau, S. Renaux, J. Chenault & G. Guillaumet Institut de Chimie Organique et Analytique, UMR CNRS 6005, Université d’Orléans, BP 6759, 45067 Orléans Cedex 2, France A series of (pyrazol-4-yl)-1,3,4-oxadiazoles and 1,3,4-oxadiazolines are described. These compounds are all synthesized in one or two steps from the hydrazide 2.

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The Reaction of Alkenes with AgNO2/TMSCL: The Synthesis of 1,2,5-Oxadiazole-2-Oxides (Furoxans) Via Nitroso Nitrates

A.S. Demir & H. Findik Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey The reaction of AgNO2/TMSCl with olefins affords nitrosonitrate, which are converted into a-nitroximes in good yield. Both nitrosonitrate and nitroximes are converted with acids into furoxane in high yield.

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The Chiral N-Monosubstituted 1,2-diphenyl-2-aminoethanols Promoted Enantioselective Diethylzinc Addition to In Situ Formed Imines

W.-W. Yang, L.-F. Cun, Y.-G. Zhi, A.-Q. Mi, Y.-Z. Jiang & L.-Z. Gong Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu, 610041, China and Graduate School of Chinese Academy of Sciences, Beijing, China The use of easily accessible N-monsubstituted 1,2-diphenyl-2-aminoethanol 1b to promote the asymmetric addition of diethylzinc to the alkyl- and arylimines generated in situ from the precursors provided optically active N-diphenylphosphinylamines with enantio-slectivities of up to 96% ee

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Diastereoselective Synthesis of 3-Phosphinoxido- and 3-Phosphono-1,2,3,4,5,6-Hexahydrophosphinine Oxides as Potential Precursors of Bidentate P-Ligands

G. Keglevich, M. Sipos, V. Ujj & T. Körtvélyesi Department of Organic Chemical Technology, Budapest University of Technology and Economics, 1521 Budapest, Hungary The title compounds are synthesized by the two step conversion of 1,2-dihydrophosphinine oxides in a diastereoselective manner. One of the diphosphines obtained after deoxygenation was a suitable bidentate P-ligand to form a chelate complex with PtCl2(PhCN)2.

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Dinucleoside Analog Synthesis Via Microwave Activated Cross Coupling Metathesis

L. Colombeau, R. Zerrouki, P. Krausz & Y. Champavier Laboratoire de Chimie des Substances Naturelles, Faculté des Sciences et Techniques, 123 Avenue Albert Thomas, F-87060 Limoges, France This paper describes a convenient procedure for the synthesis of dinucleosides via cross metathesis using microwave activation.

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Synthesis of 2,3,4-Trisubstituted Chromans Via Nucleophilic Addition of N-, C-, and S-Nucleophiles to 3-Nitro-2-Trihalomethyl-2H-Chromenes. Stereochemical and Conformational Preferences

V.Y. Korotaev, V.Y. Sosnovskikh, I.B. Kutyashev & M.I. Kodess Department of Chemistry, Ural State University, 620083 Ekaterinburg, Russian Federation 2,3,4-Trisubstituted chromans synthesis via the nucleophilic addition of N-, C-, and S-nucleophiles to 3-nitro-2-trifluoro(trichloro)methyl-2H-chromenes have been developed. Stereochemical and conformational preferences of these compounds were studied.

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A Facile Synthesis of N,N’-Bis[Formamidine]Ureas and Symmetrical N,N’-Disubstituted Formamidines

D.D. Díaz & M.G. Finn *Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, USA The reactivity of N,N'-bis[(E)-dimethylamino-methylene]urea (1) with amines is described. Selective exchange of one of the N,N-dimethylamino fragments occurs with benzylic amines, allowing the formation of 1-(alkylamino-methylene)-3-dimethylaminomethylene ureas as analytically pure precipitates in modest yields. Under acidic conditions, the urea fragment acts as a leaving group leading to the formation of symmetrical N,N'-disubstituted formamidines.

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Scope and Limitations of an Efficient Peptide Coupling Method for the Synthesis of N-Furylamino and N-Feruloylamino Acid Derivatives. Application to the Synthesis of Natural Antioxidant trans-Clovamide

C. Salmi, J.M. Brunel, N. Vidal & Y. Letourneux Laboratoire Synthèse et Etude de Substances Naturelles à Activités Biologiques (SESNAB), IMRN INRA 1111, Faculté des Sciences et Techniques de St Jérôme, Université Paul Cézanne, Avenue Escadrille Normandie Niémen, 13397 Marseille cedex 20, France Influence of numerous parameters (solvent, base, coupling reagent) in the coupling of conjugated carboxylic acid with methyl ester amino acids hydrochloride, allowing the synthesis of various substituted amino acid derivatives, has been investigated and is illustrated in the synthesis of natural trans-clovamide.

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Short Synthesis of the Selective Rho-Kinase Inhibitor Y-27632 and of Its Enantiomer

D. Belotti, J.L. Peglion & J. Cossy Laboratoire de Chimie Organique associé au CNRS, ESPCI, 10 rue Vauquelin, 75231 Paris Cedex 05, France The synthesis of Y-27632 has been achieved in 8 steps from trans-1,4-cyclohexanedicarboxylic acid by using a diastereoselective reductive amination of a ketone.

A Simple Asymmetric Synthesis of 4-Substituted-2-Oxazolidinones

V.J. Sattigeri, A.S.S.V. Srinivas, A. Soni, J.M. Khanna & A. Mehta *Department of Medicinal Chemistry, Ranbaxy Research Laboratories, Plot no 20, Sector 18, Udyog Vihar, Gurgaon -122001, Haryana, India A novel and efficient synthesis of 4-substituted 2-oxazolidinones that utilizes Sharpless asymmetric dihydroxylation of O-allylcarbamates and further intramolecular cyclization as key steps is described.

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Unusual Dimerization of 3-Methylphenalen-1-One, Leading to a Chiral Heptacyclic Oxocin

S. Pogodin, M. Thirumalaikumar, S. Cohen & I. Agranat Department of Organic Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel A diastereoselective reaction of 3-methyl-1H-phenalen-1-one with Lawesson's reagent afforded 8a,15a-dihydro-7,8a,16-tri- methyl-7,16-epoxy-7H,15H,16H-naphtho[1,8-ef]phenaleno[1,2-b]oxocin-15-one in 82% yield. The structure of a single enantiomer of the oxocin (7R, 8aR, 15aR, 16S or 7S, 8aS, 15aS, 16R) was elucidated by X-ray crystallography.

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A Convenient, Highly Versatile Iodination Method of Alcohols Using Cesium Iodide/p-Toluenesulphonic Acid

K.M. Khan, Zia-Ullah, S. Perveen, G.M. Maharvi, S.T.A. Shah, N. Ambreen, M.I. Choudhary, Atta-ur-Rahman & W. Voelter 1 HEJ Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan 2 Abteilung für Physikalische Biochemie des Physiologisch-chemischen Instituts der Universität Tübingen, Hoppe-Seyler Straße 4, D-72076, Tübingen, Germany In situ generation of hydrogen iodide from cesium iodide/p-toluenesulphonic acid was found to be an attractive reagent for the conversion of alkyl, allyl and benzyl alcohols to their corresponding iodides in different solvents under mild conditions.

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Use of Alkoxyallene Oxide and Titanium Tetraiodide/Titanium Tetraisopropoxide for the Conjugate Addition Reaction of Alkoxyacetone Enolate

M. Shimizu & S. Itohara Department of Chemistry for Materials, Mie University, Tsu, Mie 514-8507, Japan An enolate synthon of alkoxyacetone was regioselectively generated using alkoxyallene oxide and titanium tetraiodide/titanium tetraisopropoxide, and the subsequent conjugate addition reaction with enones gave 4-alkoxy-1,5-diketones in good yields.

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Regioselective Ring Opening of Oxiranes to Halohydrins with Tetrabutylammonium Halide in Water in the Presence of b-Cyclodextrin

K. Surendra, N.S. Krishnaveni, V.P. Kumar, Y.V.D. Nageswar & K.R. Rao Organic Chemistry Division-I, Indian Institute of Chemical Technology, Hyderabad-500 007, India A novel reagent tetrabutylammonium halide has been utilized for the highly regioselective ring opening of oxiranes to halohydrins at room temperature in good yields involving b-cyclodextrin in aqueous medium.

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Electrophilic Substitution In Azines

M. D’Auria Dipartimento di Chimica, Università della Basilicata, Via N. Sauro 85, 85100 Potenza, Italy The low reactivity of pyridine, pyridazine, pyrazine, and pyrimidine towards electrophilic substitution reactions can be explained assuming a frontier orbitals control of the reaction. The HOMOs of these substrates are not p orbitals.

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Sulphamic Acid (H2NSO3H) Catalysed One Pot Synthesis of 3,4-Dihydropyrimidin-2(1h)-Ones and their Thione Analogues

S.A. Kotharkar, M.R. Jadhav, R.R. Nagawade, S.S. Bahekar & D.B. Shinde Department of Chemical Technology, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad - 431004 (M.S.), India A simple and general method for the synthesis of 3,4-dihydropyrimidin-2 (1H)-ones and thiones with high yields (90-95%) and shorter reaction times (45-90 min.) by applying Biginelli reaction using sulphamic acid as catalyst is developed.

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Exploration of Synthetic Pathways to Unprecedented Terpenyl Thioglycosides

M.-J. Bourgeois, D. Gueyrard, E. Montaudon & P. Rollin Institut de Chimie Organique et Analytique, UMR-CNRS 6005, Université d’Orléans, B.P. 6759, 45067 Orléans Cedex 2, France Using 2,3,4,6-tetra-O-acetyl-1-thio-b-D-galactopyranose 1 as a model thioglycosyl donor, four different synthetic routes were explored to produce several types of original monoterpenyl thioglycosides.

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