Sökning: "kinetic isotope effects"

Visar resultat 1 - 5 av 23 avhandlingar innehållade orden kinetic isotope effects.

  1. 1. Isotopes as Mechanism Spies : Nucleophilic Bimolecular Substitution and Monoamine Oxidase B Catalysed Amine Oxidation Probed with Heavy Atom Kinetic Isotope Effects

    Författare :Susanna MacMillar; Olle Matsson; Anita Hussénius; Daniel M. Quinn; Uppsala universitet; []
    Nyckelord :Organic chemistry; nucleophilic bimolecular substitution SN2; kinetic isotope effects; precision conductometry; monoamine oxidase B MAO B; reaction mechanism; carbon 11C 14C kinetic isotope effect; ion pairing triple-ion formation; para-substituted benzyl chlorides; tetrabytylammonium cyanide; Organisk kemi;

    Sammanfattning : This thesis concerns the study of reaction mechanisms by means of kinetic isotope effects (KIEs). Studies of the nucleophilic bimolecular substitution (SN2) reaction had the dual purpose of improving our fundamental understanding of molecular reactivity and assessing the ability of kinetic isotope effects to serve as mechanistic tools. LÄS MER

  3. 2. Pea carbonic anhydrase : a kinetic study

    Författare :Inga-Maj Johansson; W. Richard Chegwidden; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pisum sativum; carbonic anhydrase; kinetic studies; site-directed mutagenisis;

    Sammanfattning : The enzyme carbonic anhydrase (CA), catalysing the interconversion between CO2 and HCO3', has long been known to be present in plants as well as in animals. Several of the animal isozymes, but none of the plant CAs, have been extensively studied. LÄS MER

  4. 3. Substituent and solvent effects on 1,3-hydron transfer in the indene system : a study of enantioselectivities, kinetic isotope effects, and catalyst conformations

    Författare :Marie Aune; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : .... LÄS MER

  5. 4. 11C/14C and 18F/19F kinetic isotope effects : methods, measurements and calculations

    Författare :Svante Axelsson; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : .... LÄS MER

  7. 5. Concerted or Stepwise? : β-Elimination, Nucleophilic Substitution, Copper Catalysed Aziridination and Ruthenium Catalysed Transfer Hydrogenation Studied by Kinetic Isotope Effects and Linear Free-Energy Relationships

    Författare :Per Ryberg; Heinz F. Koch; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Kinetic isotope effect; linear free energy relationship; elimination; substitution; aziridination; transfer hydrogenation; Organisk kemi; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis describes the use of kinetic isotope effects, linear free energy relationships and stereochamical studies to distinguish between different mechanistic alternatives and to obtain information about transition state structure.In the first part fluorine and deuterium kinetic isotope effects were determined for the base promoted HF elimination from 4-fluoro-4-(4’-nitrophenyl)butane-2-on. LÄS MER