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Organic Halides (organic + halide)
Selected AbstractsPalladium-Catalyzed Intermolecular Three-Component Coupling of Organic Halides with Alkynes and Alkenes: Efficient Synthesis of Oligoene CompoundsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2007Kana Shibata Abstract The intermolecular three-component coupling of aryl or vinyl halides, diarylacetylenes, and monosubstituted alkenes effectively proceeds in the presence of palladium acetate, lithium chloride, and sodium bicarbonate as catalyst, promoter, and base, respectively, in aqueous DMF or DMSO to produce the corresponding 1,3-butadiene or 1,3,5-hexatriene derivatives. Use of dienyl bromides allows the coupling to afford 1,3,5,7-octatetraenes. Under the present catalytic conditions, fulvene derivatives are also formed efficiently by the 1:2 coupling of vinyl bromides and diarylacetylenes without adding the alkenes. [source] ChemInform Abstract: Microwave Assisted Solvent-Free Oxidation of Organic Halides Using Aqueous Hydrogen Peroxide.CHEMINFORM, Issue 28 2008Jitender M. Khurana Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Microwave-Assisted Kornblum Oxidation of Organic Halides.CHEMINFORM, Issue 17 2008Gang Xu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Synthesis of Indenes via Palladium-Catalyzed Carboannulation of Diethyl 2-(2-(1-Alkynyl)phenyl)malonate and Organic HalidesCHEMINFORM, Issue 36 2006Li-Na Guo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] A Novel Photoinduced Reduction System of Low-Valent Samarium Species: Reduction of Organic Halides and Chalcogenides, and Its Application to Carbonylation with Carbon Monoxide.CHEMINFORM, Issue 16 2004Yukihito Sumino Abstract For Abstract see ChemInform Abstract in Full Text. [source] Highly Substituted Furans from 2-Propynyl-1,3-dicarbonyls and Organic Halides or Triflates via the Oxypalladation-Reductive Elimination Domino Reaction.CHEMINFORM, Issue 43 2003Antonio Arcadi Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Palladium-Catalyzed Three-Component Assembling of Allenes, Organic Halides, and Arylboronic Acids.CHEMINFORM, Issue 27 2002Tai-Hsiang Huang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis of 3,4-Disubstituted Isoquinolines via Palladium-Catalyzed Cross-Coupling of o-(1-Alkynyl)benzaldimines and Organic Halides.CHEMINFORM, Issue 18 2002Guangxiu Dai Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Palladium-Catalyzed Cross-Coupling Reaction of Alkenyldimethyl(2-pyridyl)silanes with Organic Halides: Complete Switch from the Carbometalation Pathway to the Transmetalation Pathway.CHEMINFORM, Issue 38 2001Kenichiro Itami Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Samarium Diiodide-Mediated Intermolecular Coupling of Organic Halides with Cyclic Imides.CHEMINFORM, Issue 20 2001Sorin Farcas Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Studies on Pd0 -Catalyzed Cyclization of N -3,4-Alkadienyl Toluenesulfonamides with Organic Halides: Selective Synthesis of 2,3-Dihydropyrroles, 1,2,3,6-Tetrahydropyrridines, and AzetidinesCHEMISTRY - A EUROPEAN JOURNAL, Issue 1 2007Shengming Ma Prof. Abstract The palladium-catalyzed coupling,cyclization of ,-amino allenes with organic halides ranging from aryl halide to 1-alkenyl halide was studied. 2,3-Dihydro-1H -pyrroles were obtained by reaction of 3-substituted-5-unsubstituted-3,4-allenyl amides under conditions A, while the reaction of 5-substituted-3,4-allenyl amides afforded 1,2,5,6-tetrahydropyridines and/or azetidines with high de under conditions B or C. The skeleton and relative configuration of the six-membered products were established by the X-ray diffraction studies of 10,ka. Allenyl amide 4,q reacted with 1,4-diiodobenzene 6,r to afford double cyclization product 15. The structure of its major stereoisomer was also determined by the X-ray diffraction study. [source] Metal-Mediated Formation of Carbon,Halogen BondsCHEMISTRY - A EUROPEAN JOURNAL, Issue 17 2008Arkadi Vigalok Prof. Dr. Abstract Organic halides represent basic starting materials for numerous metal-catalyzed organic transformations. Generally, the carbon,halogen is broken in the first step, that is, an oxidative addition reaction, of the catalytic cycle. On the other hand, very little is known about the reverse reaction, carbon,halogen reductive elimination from a transition-metal center. In this Concept article, we describe the examples of C(sp3)halide and C(sp2)halide reductive-elimination reactions which demonstrate that this type of reactivity can be quite common in organometallic chemistry. Although the thermodynamic driving force for the formation of carbon,halogen bonds is relatively small, the kinetic barrier for these reactions can also be low. Thus, Chalide reductive elimination can compete favorably with the more established organic transformations, such as CC reductive elimination. [source] Single-Electron-Transfer Reactions of ,-Diimine dpp-BIAN and Its Magnesium Complex (dpp-BIAN)2,Mg2+(THF)3EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2006Igor L. Fedushkin Abstract The reactions of (dpp-BIAN)Mg(THF)3 (1) {dpp-BIAN = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene} with ethyl halides EtX (X = Cl, Br, I) in hexane proceed by single-electron transfer (SET) from the metal complex to the organic halide. Complexes [(dpp-BIAN)(Et)]MgX(THF)n [X = Cl, n = 0 (2); X = Br, n = 2 (3); X = I, n = 1 (4)] are the products of ethyl transfer to an imine carbon atom of a coordinated diimine ligand. The compound [(dpp-BIAN)(Et)]MgBr (3a) was obtained from the reaction of free dpp-BIAN with ethylmagnesiumbromide in hexane. In this case SET from the Grignard reagent to the neutral diimine takes place. Compounds 2,4 and 3a were isolated as crystals and characterized by 1H NMR spectroscopy. The molecular structure of 3 was determined by single-crystal X-ray analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis of (Vinylidene)- and (Cyclopropenyl)ruthenium Complexes Containing a Tris(pyrazolyl)borato (Tp) LigandEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2004Yih-Hsing Lo Abstract A convenient high-yield route to [Ru(C,C,Ph)(Tp)(PPh3)2] [2; Tp = HB(pz)3, pz = pyrazolyl] has been found through the intermediacy of [RuCl2(Hpz)2(PPh3)2] (1). This complex is readily obtained on treatment of [RuCl2(PPh3)3] with 2 equiv. of pyrazole in boiling THF. The molecular structures of complexes 1 and 2 have been confirmed by single-crystal X-ray diffraction analysis. A number of new cationic vinylidene complexes [Ru{=C=C(Ph)CH2R}(Tp)(PPh3)2]+ [3a, R = CN; 3b, R = HC=CH2; 3c, R = CH=C(CH3)2; 3d, R = Ph; 3e, R = C(O)OMe] have been prepared by electrophilic addition of organic halides to complex 2. The deprotonation reaction of 3a yields the cyclopropenyl complex 4a. One phosphane ligand of 4a is remarkably labile, being replaced by donor ligands L to yield diastereomeric mixtures of the cyclopropenyl complexes 5a,5d mostly in an approximate 4:1 ratio. The cyclopropenyl rings in 4a and 5a are susceptible to ring opening by I2. In addition, treatment of 4a with nBuNC in the presence of MeOH results in substitution of a phosphane ligand by nBuNC followed by protonation of the three-membered ring by MeOH. This is then followed by addition of methoxide to give the vinyl ether complex [Ru{C(OMe)=C(Ph)CH2CN}(Tp)(PPh3)(nBuNC)] (8a). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Highly Stereoselective Metal-Mediated Entry to Functionalized Tetrahydrothiophenes by Barbier-Type Carbonyl-Addition ReactionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2008Benito Alcaide Abstract Reactions of tetrahydrothiophene-3-carbaldehydes with stabilized organometallic reagents were investigated in aqueous media. Tetrahydrothiophene-3-carbaldehydes and a variety of stabilized organic halides undergo stereocontrolled coupling under Barbier-type conditions in the presence of different metals (zinc, tin, indium) and additives [ammonium chloride, hydrobromic acid, hafnium(IV) chloride, bismuth(III) chloride]. The regiochemistry of the carbonyl addition processes, when applicable, was excellent.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Selective organic synthesis through generation and reactivity control of hyper-coordinate metal speciesTHE CHEMICAL RECORD, Issue 6 2008Tamejiro Hiyama Abstract This paper is a review of my 40 years of research at Kyoto, Sagamihara, and Yokohama, all based on the generation of hyper-coordinate metal species such as ate complexes and pentacoordinate silicates. The topics are: (i) carbenoid reagents for carbon,carbon bond-forming reactions, (ii) nucleophilic substitution at acetal carbons using aluminate reagents, (iii) preparation of magnesium enolates and its reaction with nitriles, (iv) Cr(II) reagents for reduction of organic halides and highly selective carbon,carbon bond formation, (v) organic synthesis with organosilion reagents/fluoride ions, (vi) cross-coupling reaction of organosilicon compounds, and (vii) silicon-based conjugate addition to ,,,-unsaturated carbonyl acceptors. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 337,350; 2008: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20162 [source] Studies on Pd0 -Catalyzed Cyclization of N -3,4-Alkadienyl Toluenesulfonamides with Organic Halides: Selective Synthesis of 2,3-Dihydropyrroles, 1,2,3,6-Tetrahydropyrridines, and AzetidinesCHEMISTRY - A EUROPEAN JOURNAL, Issue 1 2007Shengming Ma Prof. Abstract The palladium-catalyzed coupling,cyclization of ,-amino allenes with organic halides ranging from aryl halide to 1-alkenyl halide was studied. 2,3-Dihydro-1H -pyrroles were obtained by reaction of 3-substituted-5-unsubstituted-3,4-allenyl amides under conditions A, while the reaction of 5-substituted-3,4-allenyl amides afforded 1,2,5,6-tetrahydropyridines and/or azetidines with high de under conditions B or C. The skeleton and relative configuration of the six-membered products were established by the X-ray diffraction studies of 10,ka. Allenyl amide 4,q reacted with 1,4-diiodobenzene 6,r to afford double cyclization product 15. The structure of its major stereoisomer was also determined by the X-ray diffraction study. [source] | ||||||||||||||||||||||