Sökning: "substitution reaction"

Visar resultat 11 - 15 av 127 avhandlingar innehållade orden substitution reaction.

  1. 11. Copper-Mediated Vicarious Nucleophilic Substitution

    Författare :Olof Haglund; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis suggests and examines a novel approach for copper-mediated cross-couplings. We call this mechanistic approach copper-mediated vicarious nucleophilic substitution. Our hypothesis is that copper-promoted cross-couplings proceed via an intermediate s-adduct, a Meisenheimer adduct. LÄS MER

  3. 12. Coordination chemistry of late transition metals with PCP ligands. Synthesis, catalysis and mechanism

    Författare :Daniel Olsson; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organisk kemi; Organometallic chemistry; Metallorganisk kemi; Organic chemistry; Oorganisk kemi; Inorganic chemistry; Suzuki reaction; Stille reaction; catalysis; cyclometalation; C-H activation; PCP complex; POCOP ligand; PCP ligand; iridium; palladium; platinum;

    Sammanfattning : Abstract The work presented in this thesis discusses synthesis of PCP-complexes and utilisations of such organometallic compounds in catalysis. The complexes, obtained by intramolecular Csp3-H activation, are based on the metals palladium, platinum and iridium. LÄS MER

  4. 13. Structure-Reactivity Correlations for Reactions of Palladium(II) and Platinum(IV) Complexes

    Författare :Tiesheng Shi; Kemiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; thiol; l-methionine; maleic acid; carboxylic acid; thioether; platinum IV ; palladium II ; linear free energy relationship; volumes of activation; structure-reactivity correlation; reduction; substitution; equilibria; kinetics; mechanism; glutathione; Animal physiology; Djurfysiologi;

    Sammanfattning : The kinetics and mechanism for substitution reactions on tetraaquapalladium(II) by an extended series of thioethers, a great number of carboxylic acids, and olefins have been studied by use of UV-VIS, stopped-flow, and high-pressure stopped-flow spectrophotometry and NMR spectroscopy. Second-order rate constants k and activation parameters (activation enthalpies, entropies, and volumes) for formation of monodentate 1:1 complexes have been determined. LÄS MER

  5. 14. Diaryliodonium Salts : Development of Synthetic Methodologies and α-Arylation of Enolates

    Författare :Marcin Bielawski; Berit Olofsson; Antonio Togni; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Hypervalent Iodine Compounds; One-Pot Synthesis; Regiospecific Synthesis; Aromatic Substitution; Aryl Iodides; Arenes; Boronic Acids; Heteroaromatics; Arylations; Reaction Mechanisms; Density Functional Calculations; Large Scale Synthesis; Organic synthesis; Organisk syntes; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis describes novel reaction protocols for the synthesis of diaryliodonium salts and also provides an insight to the mechanism of α-arylation of carbonyl compounds with diaryliodonium salts.  The first chapter gives a general introduction to the field of hypervalent iodine chemistry, mainly focusing on recent developments and applications of diaryliodonium salts. LÄS MER

  7. 15. Thermoelectric Ba8Ga16Ge30 clathrates for waste heat recovery

    Författare :Daniel Cederkrantz; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; thermal stability; substitution; thermal conductivity; Seebeck coefficient; electrical resistance; Clathrates; Ba8Ga16Ge30; waste heat recovery; semiconductors;

    Sammanfattning : The modern, highly industrialized, society of today requires huge amounts of energy to function. This has resulted in a heavy dependence on the very energy efficient fossil fuels, a source of energy which of course is not infinite and we are slowly approaching the day when oil runs out. LÄS MER